the new and improved brushless electric scooter power system guide

In 2008, I wrote a guide on the instructions on upgrading your small personal electric vehicle power system.
This is an introductory book on the basics of electric vehicle power systems, offering resources and tips specifically for small electric scooter conversions.
So far, its rating is stable.
I don\'t know if you can write so much on instructures without telling anyone how to build anything, and still get the perfect review.
I am pleased to report that in 2011, three years later, a compact, powerful and efficient electric vehicle drive system was established for local commuting (
For example, your campus, community, or city)
Now, it\'s cheaper and easier to use R/C amateur hardware and dedicated EV components than ever before.
Price competition, new technologies, and a simple increase in manufacturing and material resources mean that almost everyone now has the ability to build an electric personal transport device.
I would assume that you already know the basic parts of electric vehicles or have built them before.
If not, you are welcome to refer to my previous instructions on this topic (linked above)
, Or check out one of the many great instructions on the EV system.
This construct is intended as a collection of resources, so component selection, specific vendors, design policies, and other high
Level consideration.
It will also provide tips and tricks I found or passed on to me about making small electric scooters.
The guide will publicly calibrate said scooter as I prefer electric bikes, although many suggestions are as relevant as e-bikesbikes.
This should also help for occasional quirky electric skateboards or other unconventional vehicles.
The format of Instructable is mainly one or two pages on each major component of EV-
Such as motor, controller, battery and transmission system (
And related mechanics).
I will then introduce some designs that are relatively easy to implement and make suggestions for fully customized vehicles (i. e.
Not conversion).
My previous note focused on re-leveraging the R/C hobby, namely, model aircraft, vehicle propulsion components.
It will also account for a large part of this.
Why on earth, when the Earth works properly, do you use parts designed for things that are technically not supposed to touch the earth?
The highest power of R/C aircraft components-to-
The weight power system is easily accessible to ordinary consumers.
For the eternal pursuit
With the increase in flight duration, model size and acrobatic performance, the R/C aircraft world has pushed most components such as motors and motor controllers to the limit of achievable power density.
The performance of ordinary brushless aircraft motor greatly exceeds that of ordinary ferrite-
Electric bike or electric bike magnet, DC Brush
It\'s usually three or four times.
Size and weight of 500 W electric scooter motor (
About 3 inch in diameter, about 4 inch in length and about 4 pounds in weight)
, The sample motor shown at the bottom can handle 2-3000 watts (i. e.
3 to 4 horsepower)
Peak power throughput up to 6,000 W.
The emergence of high-performance lithium-ion batteries for mass production is another factor.
A modern lithium polymer (
More about the difference between different lithium flavors! )
An American-sized battery. S. house brick (about 1. 3 liters)
In the case of the usual lithium polymer energy density of 300 Wh/L, it can be stored up to 240 W hours and discharged for several minutes at several kilowatts.
No traditional leadership
Acid, even nickel
This can be done with the chemical battery system.
It is true that there are shortcomings in having such a dense energy source that these problems will be solved, but the fact is there in the numbers.
Part of my interest in engineering is to use these increased power densities to make more compact but still practical vehicles.
For example, I have been working on a possibility of a micro hub motor, only with a brushless technology. . .
Electric skates are much less used.
Most people still think electric scooters are big and low
Leading Performance-
Sour battery-powered monsters, left to too big kids in the backyard to run efficiently.
While this may be true for most products sold commercially for cost reasons, if you build one yourself, there is no reason not to expect better.
R/C aircraft components are the best power-to-
Power System Price, cycle.
You will notice that I left the fine print \"commonly used\" there because there are things that are more core than cheap brushless motors in terms of power density.
The problem is, you can\'t buy it.
It\'s not easy. it\'s definitely not cheap.
However, since the R/C model has become so prolific, parts are easy to buy on the Internet and very cheap.
Today, most of the R/C parts are made in China and other East Asian countries and are sold directly by distributors in these regions.
Even when I wrote my previous work three years ago, it wasn\'t as real as it is now.
For most of the past decade, the electric flight market has been high.
The market of European manufacturers, so it is very expensive and unique.
In this era, there are two well-known automobile manufacturers in the US market: Astroflight and Aveox (
Seems to have left the hobby market)
And probably the Neu Motor Company.
While the most hardcore aeromodellers still insist on using European and American brands and companies with the highest performance, most run some cheap East Asian power systems.
For custom small vehicles, it is difficult to find parts with better price numbers.
Depending on your power needs, a motor with enough power to drive the vehicle will run between $40 and $100.
The controller that can run the car will be around $50 to $150.
Still, the battery is still a big cost breaker for electric vehicles, but the price of a typical aircraft lithium polymer battery pack is between $0. 40 to $0. 70 per watt-hour .
There can be about 150 to 200 watts of battery on a scooter, so it is expected to be about $70
100 of commonly used batteries.
As I will show in more detail, you can assemble a power system of about 1500 W for $200 to $300
This works for everything if you are good at shopping, even including batteries and chargers.
All of this looks like cheap airplane parts and is the way to go in the future.
However, they also have their own shortcomings.
Unfortunately, the R/C aircraft components are often very crude and somewhat fragile. Let\'s face it -
In the purely mechanical sense, the aircraft is easy to handle.
The required torque and power increase directly as the speed increases, so there is no static or lockingrotor (stall)
Conditions to worry about, unlike vehicles that require maximum torque at zero speed to accelerate from a stationary state.
The plane should never hit something, be bound by cracks in rocks and sidewalks, and should not be pushed by hanging actions.
What is more important is the light weight.
As a result, model motors typically use thin metal and plastic as well as undersized bearings and shafts to make the weight as light as possible.
Substantard metal alloy
Such as soft aluminum for construction)
It is common in \"cheap\" car structures.
The R/C Power Controller is usually single
PCB transactions, which use the smallest possible number of support components in the design to encapsulate power semiconductors and logic together, and can only achieve their ratings in a constant airflow (
For example, you know, the draft of the propeller)
And is rated under the peak power processing capacity of the semiconductor.
One of the main themes I\'ll talk about later is that you have to laugh at everything.
For electric vehicles, the rating of aircraft parts, especially cheap parts, is often unrealistic.
To make matters worse, the ordinary aircraft lithium-ion battery pack does not have a hard shell.
Lipo batteries are small bags of volatile electrolyte and active alkaline metal.
I don\'t know who is a good idea to make a battery without a shell, but due to the abuse of the vehicle, the battery has to be properly installed and proven from the impact, the impact, and the weather
For these reasons, I am even a little afraid of recommending lithium batteries to the public.
You were warned.
Overall, though, I think my point is clear: for those looking to start experimenting with electric vehicle technology, the R/C model aircraft components are a good economic option.
This may not be the best solution for people looking for reliable maintenancefree, long-
Life commuter vehicles.
Many R/C components are definitely not manufactured to vehicle specifications and may fail or become picky for a period of time.
There must be a solution for commercial electric vehicles and even plugsand-play -
But I think if you read this you will feel a little bit adventurous.
The dominant type of motor found today in the aerospace model world is called the outrunner motor.
The first image actually shows the first result I got when searching for \"outrunner\" on Google images and is very typical of most results.
Install Outrunner, so if the name hasn\'t been revealed yet, the coolest thing about Outrunner is that the housing of the motor is a rotating part.
In the first picture, only the panel of the motor-
Part of the wire-
Is fixed, this is the part that is installed on the solid.
Otherwise, the shiny golden Bell and the rest of the Silver Bell will rotate.
This often makes the motor unsuitable for traditional \"DC\" installation methods such as fixture installation or double
Installation is supported.
The idea of outrunner in Aeromodelling is that you can install the propeller directly at the rotor bell end.
However, for electric vehicles, it is a bad idea to install the sprocket, pulley or wheel directly to the motor in this way.
The reason is shown in figure 2.
The Bell shaft bearing is an effective cantilever, which means a strong side load (
Just like pulling the chain, belt, or wheel load)
Can bend the whole motor
The longer the motor housing, the worse the effect.
Instead, with the exception of the smallest motor, all Motors hang the shaft on the other side of the motor so that it can be installed and used as usual.
So far, the radial load part you want to install is like a sprocket
For this purpose, the sprocket and pulley or gear can usually be obtained by purchasing stock with the right hole size.
The pioneer of reading Outrunners is usually a certain value name similar to toAA-BB-C(Y/D)
There are two overlapping, almost non-distinguishing, somewhat conflicting systems about the meaning of letters.
The first is the stator-
Reference System.
In this system: 1.
The first number AA represents the stator diameter in mm.
This is the active part in the motor that produces all the torque, so this is similar to selling the car by engine displacement. 2.
The second digit BB represents the length of the stator (stack height)
Or the length of the magnet. 3.
The third number C may be a low number (
Single digits of 20 s)
, Indicates the number of wire loops per stator pole.
If it is a high number (
Dozens to hundreds)
It is the \"Kv\" constant of the motor, or the voltage constant in RPMs/V 4.
Optional Y or D indicates winding termination Y or Delta-
For the same number of turns, Y-
For the same current consumption, the terminated motor has a slower rotation speed and a larger torque, but a higher voltage is required to achieve the current consumption.
This is a design trade-off, but the vast majority of the R/C output is Delta terminated for convenience.
Second, the motor-
Reference system, which is more common for cheap motors, I can only assume that this is a strategy to enlarge the apparent size of the motor. 1.
The first digital AA now refers to the total diameter of the motor in millimeters. 2.
The second digital BB is the total length of the motor housing, minus the shaft from front to back.
The third and fourth figures usually remain the same. . . .
So how do you judge which is which?
If it is not explicitly given to you as a stator diameter, it may be the latter system.
The most sure way is if you have two data points --
Stator and outer diameter.
List of typical Statorto-
Motor diameter cross-correlation of typical vehicles
Size motor is given below: 42 to 45mm stator> 50 to 55mm motor housing 50 to 52mm stator> 63 to 65mm motor housing 68 to 70mm stator> 80 to 85mm motor housing size is 60mm (motor)
There are enough diameter grades.
A good seller will give at least two important specifications that you can use to determine the basic drive system parameters. 1.
Kv rating is the speed at which the motor rotates per applied voltage.
Instead, if you rotate the motor, how many volts does it generate on its terminals.
This is largely the remainder of the DC motor era, and it rotates when you can dump the motor on the battery.
The electronic controller, such as the BLDC controller, can actually significantly change this parameter of the motor, so Kv is just a rule of thumb unless you are a motor engineer.
You can expect drive ratio from motor to wheel at RPM/V, system voltage (x to 1)
Wheel diameter (in inches).
Calculate the theoretical maximum speed of the vehicle.
In an ideal, frictionless world, this is a purely theoretical number.
Equation goesSpeed (mph)= [(
Speed/V * system voltage)/ (Gear ratio )]* (Diameter * pi )* (
60 minutes per hour/12 inch per foot)/ (
5280 feet per mile
A cool little resource for you to complete all of this and even provide you with acceleration and battery data is the late Steve giudd hours calculator for tentacle torque and AMP for the battle robot community, long-term competitors of robots and robots.
The site is still a resource for robot manufacturers.
It is very \"robot-oriented\" as expected, but in order to use it for vehicle calculations, simply insert your own motor statistics (
Or guess), and use 0.
If you have a single motor drive, 5 motors per side.
Please note that for the use of electric vehicles, the \"average percentage of peak consumption\" should be reduced to 5% or 10%
This is the time you spend burning out or stopping the launch.
There is a database of cataloged motors for sanity checking.
If you only have a KV rating, the only thing you can estimate is the maximum speed. 2.
The internal resistance of the motor, also known as the winding resistance, terminal resistance, etc.
It is usually a low number (less than 1)ohms .
Given this value and your system voltage, you can calculate the maximum current that the system can theoretically see based on Ohm\'s law I = V/R.
The actual current consumption will be less (
But not much)
Due to the inherent resistance of copper wire, semiconductor, switch contacts, etc. , this value is exceeded.
But it\'s still a rough number.
Also, as I just describedbuild-your-own-damned-motor-
Already written, considering the Kv of the motor in RPM/V, you can also find the torque generated by the current per ampere.
RPM/V is not an SI unit, but you can understand the voltage constant V /(rad/s);
That is, every Volt (
Radian per second).
In short, the voltage constant in V/rad/s is also Nm/A or Newton-
Meters per ampere.
Nm/A can come back directly if you have this tendency
Convert to ft-lb/A or in-
Oz/A because they are all torque units.
So if you know the IR of the motor and the voltage of your system, you can find the theoretical peak torque value of the system, which is useful for calculating the maximum acceleration: torque (Nm)= (Nm/A )* (
System Voltage/motor resistance).
This number is really very theoretical.
I will solve the special consideration of the R/C Motor near stall in a moment.
Sometimes you will also see rated power if Outrunner is larger --
Usually in a few hundred or several kilowatts.
It is important to remember that the value given is almost always the power input --
That is to say, your battery supplies power to the motor.
If you are familiar with the principle of the DC motor, you know that the motor can only output a value of 50% as a mechanical output power.
Torque multiplied by speed. (
Please read this if you don\'t).
If it\'s an ideal motor
At this point of operation, 50% or more of the input power is dissipated as heat.
Basically, the \"rated power\" number doesn\'t help much because if the motor is running in close to half of the position, it will overheat quickly.
Ultimately, the way to determine the size of the motor by power is to roughly calculate the total resistance using the resistance equation, assuming that the Cd is about 1. 0 (
For a person who stands forward)
And multiply the cruise speed you want
In the SI unit, the result is the power that the motor needs to output to keep you going at this speed.
In other words, watts = (
Newton resistance * cruise speed in meters/seconds).
From experience, this should be less than 15% of the maximum motor input power.
Why not compete?
Behind is an \"inrunner\"
The construction word of the traditional brushless motor.
In the aircraft sector, they are not very suitable for vehicle propulsion, as they rotate much faster. e.
The Kv value is very high.
Subsequently, in order to achieve the same torque level, they need more deceleration devices.
While the inrunner drive is absolutely possible, the added mechanical complexity is sub-optimal.
However, they are certainly easier to install and less susceptible to dirt and road waste in the motor.
Unlike the normal old DC motor, the brushless motor requires an electronic controller to replace the motor.
They do this differently, however, often boils down to whether the motor strategically places Hall sensors in the winding to sense the position of the magnet rotor so that the controller knows which coils to switch.
Other strategies include position encoder wheels, but Hall sensors are the most common among small motors.
The vast majority of model motors are sensor-free, and this is the first rule to remember.
Because the load that the aircraft is subjected to increases predictably as the speed increases and is zero at zero speed, almost all aircraft motors (
Outrunners in particular)
Just spin the magnet ring on the stick.
That\'s why they can make it so cheaply.
Industrial Motors for general motion control such as servo systems and robots do not need to deal with changing transient loads, so they have some kind of feedback built into them.
Typically, only models with built-in sensors are such small R/C cars and truck motors.
Sensor control is the basic method of sensor motor (
And associated controllers)
In the motor, three sensors are often located at a distance of 120 or 60 degrees, and the output is 3-bit Gray-
Like location code.
The position of these sensors depends on the winding configuration, the number of slots and the number of magnetic poles.
For more information on how this works and why it works, please see my hub motor instructions.
The advantage of the sensor phase change is that the controller always knows where the motor is.
Therefore, the sensor motor usually has a low
Speed and gear are more like classic DC motors.
There are disadvantages of sensor phase change-
A sensor failure or failure may mean that the motor controller stops running the motor.
Most cheap industrial and commercial controllers, even electric vehicle controllers, are only controlled by a state table whose input is 3 hall sensors, so sensor failure means an output errorrunning motor.
Another problem is to find the correct combination of Hall sensor lead and motor phase output
If your Motors don\'t have a controller, there are up to 12 possible ways to match them together.
Picky details aside, sensor switching is the way to achieve consistent stagnationand low-
Speed behavior, \"real\" vehicle controllers are usually sensors-commutated.
Sensor-less controle.
The R/C speed controller sensor-free controller must detect the position of the rotor by other means.
The most common method is to hit the motor randomly (
Drive two stages)
And look at the back-
The EMF on the third phase or the voltage distribution generated.
The slope of the BEMF determines the direction of movement of the motor, so which coils to switch next.
The sensor-free phase-change uses more complex position state estimator that must have some speed feedback to \"pick up \".
In other words, a sensor-free motor cannot be technically moved without having already moved.
This clearly creates difficulties for vehicles and other inertial loads.
If the initial \"bump\" is not strong enough, the motor will not be able to move to generate a meaningful voltage pulse.
For viscous loads such as propellers (
Load proportional to speed)
This is not a problem at all.
Therefore, the vast majority of R/C controllers are sensor-free.
There are sensors.
Again, for cars and trucks, as you might guess, they are like small electric cars you personally ride, inertia loads.
Sensor-less control of cars and trucks is also common, as modern motors are powerful enough to move small models with pulses in phase.
The biggest implication of sensor-free control is the suspicious availability of the blocking torque.
This makes the torque equation shown two pages ago a bit misleading.
You can\'t usually stand in a car and challenge someone to a racing race.
Sensor-free vehicles, especially those using R/C components, need to be \"started\" or \"pushed to start \".
The only real difference between sensor-enhanced sensor motors and sensor-free Motors is that. . . sensors .
You can actually use any common R/C outrunner and add Hall sensors to use with the Electric Vehicle Traction Controller.
There are many ways to attach sensor feedback to your motor: I cover installing sensors in the winding (
Inside motor)
On the instruction manual of my hub motor;
Two external mounted sensors have now been used.
You will end up with an additional 5 harness from the motor, including three hall sensor outputs, logic power supplies, and logic ground.
The Hall sensor is usually the \"open collector\" I. e.
They absorb only current.
Controller has internal pull
Built-in resistors, so it is generally not necessary to pull the hall sensor output to the logic rail internally.
However, the power supply De-coupling capacitor placed on the Hall sensor lead seems to be helpful.
Hall cables should not be wired in parallel or close to the phase conductor, because high switching current in the phase conductor can cause noise problems in the sensor cable.
Update June 2013: I hate the Outrunner Hall sensor attachment that I usually plug in, but I have successfully developed and am selling a range of Hall sensor boards and Hall sensor holders in the past few months, the size of these brackets fits several typical outrunner suspects.
Placed outside, they allow sensors-
Only motor controllers drive these motors.
See plates and brackets equal to zero design.
I designed these \"inventory solutions\" specifically for those who asked me how to add sensors to your outrunner \"!
Half the point of this guide is that I tell you to use R/C devices in unexpected ways, good or bad.
So I put together a list of guides that I found helpful.
These include design and operation, so when you assemble a vehicle using R/C components, it\'s more of a state of mind.
The more electrical cycles your controller sees, the faster it locks the AC motor (
Technically speaking, brushless motor
Details here don\'t matter)
The ratio of electric speed to mechanical speed is different.
Of the most basic 3-phase motors, there are 2 magnet poles and 3 stator slots (
In other words, three coils)
, The electrical speed is the same as the mechanical speed.
With the increase in the number of magnetic poles, the ratio of electric speed to mechanical speed will also increase
In fact, one-on-one.
A good animation of this principle can be found on the LRK website (
Those guys who make the number of high poles popular in the aviation model world)
It is important to note that the high pole number motor does not necessarily have more torque, but in a certain range, the increase of slots and poles will reduce the Kv value of the motor (
And increased the torque generated per amp so that they no longer need the gearbox to drive the propeller.
The angle the motor must move between magnets-
The stator pole alignment is small, so it is necessary to switch frequently to achieve the same displacement.
However, since the sensor-free controller relies on having a regular motor voltage waveform to \"lock\" to, this may be advantageous.
Two things to do with the motor.
As mentioned earlier, one of the facts is that the controller has to switch more in order to achieve the same displacement.
When coupled with the mass of the vehicle and the rotation inertia of the motor itself, it tends to produce a smoother BEMF profile.
The title image is a picture of the actual appearance of the motor terminal voltage distribution at runtime.
The second effect is. . .
Slowing down will also distract you from inertia.
Remember when I said that the aircraft propeller was not an inertial load? e.
Non-zero torque is required to start acceleration?
In order to approximate in the vehicle, you need to minimize the inertia seen by the motor as much as possible.
It can be seen that the apparent mass of the load seen by the motor decreases to a factor of 1/R ^ 2, where R is the deceleration ratio (i. e. R to 1).
You can already see that if you slow down the motor around 8 or 10:1, you hardly exist as far as it is concerned.
Therefore, the sensor-free transmission system benefits from a very high deceleration ratio. it is important to note that no matter how far you slow the motor down, a certain amount of drive is required to start.
This may be as little action as jumping on a slightly forward vehicle, but you can\'t just stand on top and hit the throttle, other than the ridiculous limiting situation.
It may work, but it will be unstable at first (
Phenomenon called \"positioning\" in R/C world)
And lead to high current being attracted.
Therefore, an extension attempt initiated from a static state may result in rapid ESC overheating and failure. So that means. . . Don\'t floor it. . . .
Unless the vehicle is already moving.
Low speed sensor-free operation usually requires a stable finger and may be unstable.
The controller may lose sync with the motor, which means it switches the wrong phase at the wrong time.
If you move slowly and then suddenly increase the throttle command, there may also be a loss of sync.
Most controllers assume that the motor can rotate at a certain minimum angular acceleration --
This may not be your burden.
This also causes loss of sync.
The sensor-Free R/C controller may cause an accident in the vehicle (
Or just no meaning)
Pause and low
Speed performance.
Slowing down the fast motor at a high ratio can alleviate this problem, so use it as a design consideration when running the transmission system calculation.
Since the R/C controller uses the industry \"standard\" servo pulse of hobby as input, you can\'t just use 3-
Wire potentiometer.
Signal conversion must be performed, and signal conversion can be performed in hardware or software.
Lead image is a graphic of a typical \"servo command\" Pulse
Width Pulse: 1500 microseconds is a neutral or zero speed signal, 1000 microseconds is usually a one-way full power signal, and the other is a 2000 full power signal.
When the servo system and the robot controller respond to the indicated pulse duration, the typical aircraft controller is one-way.
The most common \"default\" is that 1000uS is zero speed, 2000 us is full speed, or something like that range.
Of course, ESCs can be recalibrated to accept different endpoints at will, so the difference is basically irrelevant.
A simple \"servo tester\" is the throttle of your friendda vehicle, which is basically a knob that you can turn to produce a signal that controls the speed of the vehicle.
In the vehicle of the gasoline engine, this knob may have actually been pulled to the throttle body of the engine, but usually these days, it is an electronic signal of the engine computer.
In the Hobby world, there is a small device for sale commercially, which precisely completes the task of converting knob motion to a \"servo\" pulse, called a servo tester.
An example is shown in figure 2;
Especially this one.
To make sure your servo systems work, they are used instead of setting up the entire radio and receiver.
Please note that one (
The cheapest one sold today)
There are three outputs.
This allows you to test all 3 servo systems in the helicopter main rotor at the same time.
You only need to use one.
The coolest part of most servo testers is that you can drop 0-directly-
5 v source such as 3-
Insert the wire potentiometer or commercial vehicle throttle into the position of the knob (
It\'s a potentiometer in itself).
3rd the image shows the conversion I made to this particular servo tester model-
The 3-pin connector is connected to the commercial manual throttle (
More information about these parts).
After this stage is completed, you have a direct analog voltage to servo pulse converter that can be installed on the vehicle.
Note that these modes have different modes, such as \"neutral\" mode, which helps to maintain the servo center when adjusting the connecting rod, and the \"scan\" mode automatically completes 1000-2000uS sweep.
These modes are useless, and if accidentally selected during the operation, they may cause bad.
It is recommended to delete the button for select mode.
You can build a 100% hardware if you like to torture yourself (i. e.
Linear Integrated Circuit (caps)
Timing circuit to convert 0-
5 v refer to the appropriate servo pulse.
I link to a few of the older versions, but these days you have no reason to use a full hardware servo tester because they cost about 5 cents.
The value of the hardware part will change with the change of temperature and even humidity, and there are more parts, so it is more prone to failure.
Because the sensor-Free R/C controller cannot really control the current they send to the motor (
The current is proportional to the torque output), and low-
The speed start can be unstable and difficult to control, and it is useful to have a \"ramp\" somewhere in the throttle chain.
If there is no ramp or other type of control input damping, a sudden bumpy movement of the hand or foot may cause an unexpected response from the vehicle, such as a sudden power failure.
Not only is this difficult to operate, it can be very dangerous if you are in traffic or around others.
Slopes can be implemented both in hardware and software.
Hardware resistance-
The capacitor filter in the fourth image is a \"RC filter\" type circuit where RC is a resistor-
Capacitance, which smooth the sharp transient in the control input.
The general form of the circuit is called a low-pass filter, and its technical details are not discussed (
Wikipedia can provide better treatment than me).
The values of R and C of your choice determine the damping \"time constant\", which is only given by Trise = R * C.
No, really. that\'s it.
So in this example, a 100 K resistor along with a 10 uF capacitor forms a filter with a rise time of 1 second.
Meaning if you pull it down from a static state (
You shouldn\'t be like that anyway, right? )
It takes 1 second for the control signal to reach 63% (
Standard threshold defined by this circuit).
The true precipitation time is defined as the time required for the output to reach more than 90% of the final value and is generally accepted as 3 time constants (3 * T).
You can adjust the R and C values to achieve the speed of the filter you want.
The important thing is that the resistance is much higher (
At least 10 times)
Than the value of the throttle potentiometer, it should be at least 10 k ohms.
The reason is that if the resistance is too close to the total resistance of the pot, the potentiometer strongly affects the time constant of the filter.
I gave an example of 100, but since most of the vehicle\'s throttle is a resistance of 5 k Ohm, try using at least one resistance of 47 k.
The capacitor can be of any type of polarization or non-polarization, but please put it straight if it is polarized.
The entire circuit can be welded online with a throttle harness.
The second variant of this circuit adds
Bypass of the system so that the throttling does not increase-
This means that if you let go of the full throttle, it doesn\'t take a second for the throttle signal to slowly fall back, and it will almost immediately recover.
If the input voltage on the potentiometer side is lower than the voltage of the capacitor, the diode will turn on (
Which output is it?
Therefore, for these positions, it efficiently diverts the input to the output.
In the software, if you are making your own servo tester, it can also be implemented in the software using a micro-controller --
Like a device.
For example, the following Arduino code implements the ramp by entering an R/C Pulse on one digital pin and spitting it back to another.
This is written by Arduino and motor control guru Shane Colton. include define THR _ Max THR _ min 178 limit 870 define PWM _ Max PWM _ Min 1000 limit 2000 month SPEED_LIMIT definition.
Score definition ramp _ limit 0 for 33/full speed.
13/fraction of full speed of servo tgypwm per second; float pwm_f = (float)PWM_MIN; void setup(){pinMode(9, OUTPUT); tgypwm. attach(9); /*tgypwm.
Seconds (PWM_MAX); delay(5000); */tgypwm.
Seconds (PWM_MIN); delay(5000); Serial. begin(9600); }void loop(){
Symbol int thr = thr _ min; float thr_f = (float)thr;
Floating pwm _ target = (float)PWM_MIN;
Unsigned int pwm _ I = pwm _ min; ;
Thr = analogRead (7); thr_f = (float)(thr -THR_MIN)/ (float)(THR_MAX -THR_MIN);
Pwm _ target = thr _ f * speed _ limit *(float)(PWM_MAX -PWM_MIN)+ (float)PWM_MIN; if(
Pwm _ target> pwm _ f){
Pwm _ f = ramp _ limit *(float)(PWM_MAX -PWM_MIN)* 0. 05; }else{
Pwm _ f = pwm _ target; }pwm_i = (unsigned int)pwm_f; tgypwm.
Seconds (pwm_i); Serial. println(pwm_f); delay(50); }
While battery technology is not enough to take a seat in the car market, modern batteries are fully capable of powering individual electric vehicles.
The focus of this Instructable will now shift to a brief overview of the types of battery technologies that builders can easily access, where to get them from, how to charge and maintain them, and most importantly, how not to use them.
The first topic is lithium ion batteries of all types.
Most of the details about battery types are collected from sites like Wikipedia, so I\'m not going to do much quantitative analysis.
Forget about lead and nickel.
Still the most common small electric cars you can buy because they are cheap (and heavy. . .
Does this make them Chevrolet cars in battery world? )
I definitely have no reason to stay with the leader
Acid Battery today
If a light personal vehicle is to be crushed by 50 pounds lead, it makes little sense.
Typical small 7 to 18 am p.
When used in the case of a vehicle, the cycle life of the hourly sla is poor and the capacity of more than 80% cannot be retained for 300 charging and discharge cycles. Lead-
More suitable acid battery for long use
Terms of backup power supply. . .
By the way, this is exactly what they use most these days.
Tip: the backup power system will not move in general.
The good thing is that they are very easy to charge and the lead charger is very cheap.
If you want to kick its old school, the nickel battery is still a strong contender for the use of individual electric vehicles. They have 30-
Storage capacity increased by 60% over lead and weightfor-
The weight base can pour more Watts (
High discharge capacity)
Faster charging.
However, the Ni battery is no longer the cheapest option.
Large-capacity, low-resistance batteries are still expensive. A typical 4. 2Ah, 1.
The cost per battery for 2 v nickel metal hydrogen batteries can still reach $7 or more and you need at least dozens to make a useful package.
Many R/C vendors have completely abandoned Ni batteries from their lineup, but places like Batteryspace (
As well as any other cutting-edge companies from Chinese battery suppliers)will have them.
Battlepack is a well-known dealer who has served in the robot community for many years.
However, the NiCd and NiMH batteries are also very easy to charge and do not require a battery maintenance system.
Lithium is where it is.
I had to think about it for a while before publicly advocating the use of lithium-ion batteries because it was easy to mess them up.
With 100-
Energy density increased by 150% compared to lead
The acid provided by lithium batteries, they also bring tolerance to excess
And under-voltage, it is easier to enter the heat out of control when these conditions are reached, and the battery management system or more careful charging monitoring is required.
However, they are also the most versatile and potentially cheapest option (oddly enough)
Power your vehicle.
The following is a brief overview of the types of lithium batteries.
Lithium cobalt oxide for hard shell batteries (i. e.
Laptop battery and its similar products)
These are classic \"Lithium ion\" batteries, which are 3.
Nominal 6 volts, 4.
2 Volt charging.
The most common shape factor is the 18650 cells measured. . . .
18mm wide and 65mm long
The typical battery capacity of this size is 1. 8 to 2. 4 amp-hours today.
In fact, I\'m not going to pay too much attention to them because you usually only get loose cells (
Need to assemble
And they\'re not high either. rate discharge.
The lithium \"polymer\" soft bag cellI doesn\'t know who the idea is to cram the battery into a sandwich bag, but Lipolies is now the most common lithium battery.
They have cobalt oxide and manganese oxide, but their subtleties are negligible.
The nominal voltage is 3. 7 volts and 4.
2 volts when charging.
They are usually flat cells of various rectangular shapes.
Lipolies is now the standard for the world of R/C and I will extend that fact.
They can have incredible high discharge and charging rate tolerances, and are usually close to the theoretical maximum of 240 watts per kilogram that a lithium-ion battery may achieve today.
Because they are hobby parts for mass production, they are also very cheap.
Probably the cheapest battery option you can buy.
However, soft-
Housing, they are easily damaged and can become very dangerous if mechanical damage or short circuit.
Their high discharge capacity is also a curse, as short circuits can easily become electrical fires caused by hundreds of ampei fuels.
Lithium Nano (LiFePO4)
The latest highly commercialized lithium battery technology is LiNP battery, whose poster battery is A123 26650 (
No one but MIT.
Attached a123 System).
The \"nano-phosphate\" part refers to the use of lithium-transition-metal-
Phosphate nanoparticles are used as cathode.
Short stories have higher discharge and charging rate tolerances than the classic Li-
The tendency of Co cell and fire lighting is much smaller.
One drawback is the reduction in cost and specific energy density.
If I have to say one reason why I support lithium-ion batteries more than anything else, that is the abuse that they might be subject to because of lithium chemistry.
While no battery won\'t catch fire, charging the A123 battery is usually more delicious than the same Lipoly battery
They tend to bubble and drain the heat and electrolyte instead of burning the flame.
There must be a lot of options for making your life bag and I will talk about that.
Lithium ion battery is 3. 2 volts (or 3. 3. . . I find 3.
2 it is easier to do math)nominal, and 3. 6 to 3.
8 V charging.
All lithium chemicals need special chargers that charge with constant current constant voltage, especially life batteries need different termination voltages (A Li-
Can not use Co or Lipoly charger directly on the life package). Loose cells vs.
At the time of packsAlot, you can find loose batteries next to the battery pack.
Due to the different levels of experience of potential readers, the physical danger of using loose lithium batteries, and the special welding techniques needed to assemble the packaging, I would not advocate that people make their own battery packs here.
The prefabricated packaging will already have separate battery taps (
Critical for future battery management systems or charging balancers, please elaborate as soon as possible)
Pre-installation and wireattached.
They come with chargers and integrated BMS in some cases.
This whole explanation can be summed up as \"How to shop on Hobbyking\" because that\'s exactly what I\'m going to tell you to do.
There are several reasons why I pay special attention to the lipoly selection and the lifepo4.
First of all, they have tons of different grades, capacities and physical sizes. They are well-
Classification, customer audit system is extensive.
There is also a good battery warranty in Hong Kong.
For some time a few years ago, their battery quality control problems were poor and the quantity was too high.
However, after a few packs (
Intentionally or not)
I usually think their numbers are reliable now Oh yes they are cheap too.
When you adjust the size of the battery, here are some things to be aware.
C ratin of Batteryland, unit \"C\" is a battery capacity of amps.
In other words, for 1.
0Ah battery, 1 amp for 1C.
10C is 10 am ps, and so on.
The battery is almost always rated in some continuous and sudden situation (
Order of a few seconds)
Discharge rating. High C-
The rating unit has a stronger, thicker interconnect and is physically larger in handling power throughput.
The high C group will show less voltage drop under high current load.
You don\'t usually need crazy 40-for a battery with a reasonable capacity-
50C discharge package, more expensive.
I found that only the 30C type battery and the higher battery have copper interconnect, which is critical for high current continuous stretching.
Keep in mind that the cruise current of a small electric vehicle should be determined by the maximum continuous current of the motor (
Help to heat the motor)
And ordinary 50-
60mm motor should be 20-
Up to 30 amps, only 4 to 6C for 5Ah packaging.
However, this does not mean that you should get a cheap 15C battery, because the current demand at startup can easily exceed this level, and frequent offsets can cause the battery to overheat and have a short lifespan.
The size of the battery capacity depends entirely on the designer.
The energy required for a certain distance of the vehicle is given in Watts. Every mile (or per km)
It\'s the same unit of things-wise as (inverse)
Miles per gallon, or 100 km liters per gallon.
There are many factors at work here, including the cross-sectional area of the vehicle (drag)
Whether you go up the mountain or down the mountain, your tires are inflated, weight, road surface roughness, whether the bearings are refueled, etc.
In other words, there is no exact simple rule of thumb for the battery pack size.
However, a good resource to use as a lookup table is Austin EV EVAlbum-
You can search for vehicles similar to what you are designing to see if other builders have collected Wh/mi data.
Small electric scooters seem to travel 25 to 40 watts per mile on average.
My own RazEr hub scooter is low end (
Measure 25 Wh/mi), and melon-
Scooter is a total battery pig because it has huge motors and Norby tires at 39 to 42 Wh/mi.
Keep in mind that 100% of the nameplate capacity will never be available from the battery.
Usually, the battery is charged-
The discharge cycle in the EV world is defined as 80% charge state to 20% charge state.
When the constant current phase is over, the lithium battery completes the \"quick charge\" and then is filled about 80 to 85%.
20% is a recognized minimum safety emission threshold.
So if the battery is in normal use and charging is not allowed, you will really get about 60% of the battery (say overnight).
Parallel with multiple cells
Multiple packages in a parallel package are available as multiple units of internal parallelism (
Expressed as \"xSyP\" where P is the number of cells in a group).
While it\'s tempting to place multi-pack single cells in parallel, you have to have a dedicated charger for each packagee.
Charge management can be carried out separately for each.
In the case of parallel packaging, this is necessary because there is no guarantee that the same unit in each package is discharged at the same rate or at the same level.
If these batteries charge at the same time, then these batteries can adapt to different voltages over time.
Because lithium batteries cannot tolerate overcharge or overdischarge, it needs to be balanced regularly and it is a pain to have to balance multiple battery packs.
Guess how I know.
That\'s not to say it\'s impossible, but you should be ready to do a battery sitter every once in a while.
A better choice is to get the biggest single
You can install your phone.
If you are making your own packaging, put multiple cells together first so that they can act as a large cell.
The Balance plugsR/C package comes with a small connector that can disconnect the middle of each unit connection.
This is usually used for battery balancers that may or may not be built into the charger-
Charge more later.
The most common connector is called JST-
XH, it\'s good because it uses standard 0. 1 inch (2. 54mm)pin spacing.
Connector (as components)
Very cheap in places like Digikey and you can also buy harness, adapter etc.
It is packaged in series or in parallel.
If you are running multiple parallel packages, make sure to grab one or two parallel balance adapters (
Examples of different connectors)
Always charge for using it.
The mechanically protected lithium-polymer battery is soft and shiny, and the HK\'s lithium-phosphate flat-panel battery is no exception.
The R/C models are usually also soft and easy to insert, so this is not a problem in their intended application.
However, the vehicle is usually not very soft.
The battery must be installed properly or inside the housing or protective housing.
The entire length of the battery is always supported. It\'s not just a zipper that ties a lithium battery pack to something --
The concentrated stress of the zipper tie belt can mechanically damage the cells and may cause perforation
Like hot out of control
Never compress the battery between surfaces like too loose suspension would be bad, and squeezing the battery between two surfaces would be bad too.
Extra pressure can be placed on the roller
The edge of the sealed cell will burst, and then the bad one will happen.
Nothing sharp around the battery can not only cut off the wire and break the insulation that causes the frame power failure, but also the sharp sheet metal edge can cut off the battery.
Keep the battery away from water, road waste, etc. Water (
If you came from meSugar coated chemicals)
Penetrate into the layers of the battery pack packaging, and with the help of electrolysis, it can cause rapid corrosion of the terminals.
Ideally, the battery should be in a hard shell that is perfect for it, but it is possible to transfer all the mechanical loads of the vehicle around the battery.
If I can\'t fully emphasize this, then I can only say that people have made the entire youtube career on the basis of lighting up lithium batteries.
Enough of them-
You will be more careful.
By the way, Hong Kong has a complete set of hard shell packaging for R & D of cars (
It\'s easier to hit things).
Although I have not used them, I believe they are good things.
Based on the general assessment of the vehicles I have built or seen built, a good starting point for an electric scooter is the 5Ah pack of 6 s to 10 s (
2 packages in series may be required)
Emission specifications from 25 to 30C.
This can be bought for about $100.
This is close to $150 or $200 if you choose a cheap LiFePO (
As of this article).
In a segment of the consumer market, A123 batteries are sold in packages that integrate the battery management system and bundled chargers and are used daily by people who are not electric car nuts. That\'s high.
Cordless electric tools market.
Specifically, the dc93 60 36 V lithium-ion battery of the DeWalt 36 V power tool series has been highly praised by the crazy electric bike guy community.
Battery and charger (
Part number DC9000)
Suits are usually available on Ebay or Amazon for about $200, and the battery itself is about $120.
For 10 A123 batteries with integrated battery manager, this is quite a steal at the market price.
It is much more expensive than the Hobbyking option, but the A123 battery is of excellent quality.
However, the dc93 60 does need a bit of a hack to turn it into a full EV battery.
The battery has three terminals: 1.
Positive, directly connected to the cells inside. 2.
The negative terminal connected through the hard 15 am p fuse inside the BMS module is different from the Fuse described below.
Pulling more than 15 am ps from here will blow up the fuse. 3.
Another negative terminal connected through the internal power MOSFET.
The internal work of the BMS module recorded several hacker attacks, indicating that the FET was used as a speed controller for the tool motor.
A document detailing how to connect to BMS so that FET is on (
Higher current output is allowed)is here .
It also describes more than one
Any number of batteries can be connected and in and out of the battery \"ORing\" system.
However, I cannot guarantee this line because I have never built it.
Another option that has been verified is to simply weld the wires directly from the positive and negative terminals of the battery, completely bypassing the BMS for discharge, but continue to use it for charging.
This operation usually leaves the discharge cable off the back of the package and leaves the label and connection at the top unchanged.
The fuse is deliberately narrowed around the battery interconnect inside the battery pack, so if the current consumption is too high or the battery short circuit exceeds BMS, it acts as a fuse.
Location of battery-
Level fuse is described in detail in this RCGroups Post (
The post itself describes the complete removal of the BMS module, which is great if you want to make the package yourself, but it doesn\'t help other than that).
This narrow area can be bridged with copper de-welded weaving, ground weaving or some wires.
A big soldering iron (60 to 80 watts)
For tips with high thermal mass, apply to weld the reinforcement without heating the battery.
Many of the resources on interbikes are written by crazy electric bike enthusiasts who talk about how to chop and tighten these batteries --
And one more.
How much I love progress.
Over the past year or so, some battery companies have produced \"lead-
Basically the acid replacement \"package of Life cells in the box, with charge management circuits, making them compatible with the traditional\" dumb \"leadsacid chargers.
They usually have a good function of automatic charging cut-off, internal battery balance, fusion or protection output, and others that make your electrical system a plugand-play.
The downside, of course, is to increase costs.
Of course, they are not the best in terms of energy density either, as they are designed to be suitable for applications with existing industrial battery sizes.
I have listed some possible vendors below as well as comments and usage considerations.
K2 Energy is my favorite SLA replacement bricks at the moment as I actually have a chance to use them and they are commercially available and they are a bit inadequatethe-
Our radar battery company is called K2 Energy, but they have products. Nice product.
The models discussed are k2 b12v7eb and k2 b12v10eb, both of which are \"7Ah\" leads
Acid battery format.
The 12V10 has a parallel additional unit in the same package for higher capacity.
The rated discharge of these modules is 25A and the peak is 40A, which is enough for the average cruising vehicle, but may not be enough for the drag racing setting.
It is important to note that they have a version of the internal battery management module and there is no version of the internal battery management module.
The \"B\" in the part number indicates the existence of the BMS board.
Ordinary version (e. g. K2B12V7E)
As far as I know, this is just a box of cells.
The cost is usually $30.
40 less than the BMS version, but if you just get a box of batteries, then the cost per watt hour is not much competitive at all compared to the HK phosphate battery pack.
I \'ve taken apart a 12V7 module on my website because I\'m curious about the internal layout of the SLA replacement module, so if you want to look inside too, the post is here.
The retail price of these products is usually $140, and the retail price of 12V10 is $170.
12 V10 the cost of watt hours per dollar is actually much lower: about $1.
40/Wh for 12V10 compared to $1.
70/Wh for 12V7, the package size is the same, so I think 12V10 has an advantage in this regard.
A123 Systems my electric vehicle lab class in the spring of 2012 was partially made possible by A123 donating a complete set of alm12v7 modules.
They are their own houses.
Some SLA modules with the highest discharge level have been developed.
They also have an externally accessible fuse, which is fine because if you blow up the internal BMS on any other module, the whole module will be destroyed.
If the fuse explodes, the BMS closes until the fuse is replaced and then a charging voltage is applied to the battery, which wakes up like a Pokemon.
For students
Made vehicle, this happened several times and as a result the fuse was there and I was a little happy.
No matter how good A123 is to us, I don\'t sing their praises anymore now and point out that you can\'t buy these.
A123, in my opinion, suffers from an \"elegant American company disease\" that absolutely refuses to do business with end users and only seeks contracts from large suppliers.
You can\'t buy ALM12v7 online or through any supplier-
If you search for ALM12V7, all the links are made up of user guides and people who are provided by used or insiders.
A123 did not market these products to people who eventually actually used them.
No matter how good the product is compared to other products in the market, they are impossible to buy and therefore may not exist.
But if they are wise, I will leave this space to link to the supplier of ALM12V7s when they pop up.
* NEW * November 2012: Yes, you can buy it now!
Properly named buya123 battery.
Com website is the embodiment of the company\'s efforts to actually sell goods.
ALM modules and loose units in 18650 and 26650 sizes are available.
There is also a completely different Chinese battery World for General/non-branded SLA replacement modules.
My favorite Chinese Battery front company Battery Space has a whole page.
These ingredients that may be sold separately elsewhere on the website (
PCM Board).
I haven\'t seen these or used them myself, so I can\'t recommend them anyway.
Many of them seem to have a lower capacity, which may make them less suitable for vehicle use.
Unlike nickel-cadmium and lead-acid batteries, you can\'t throw the lithium battery pack on a power supply with a fixed voltage, and then trickle it up until the charge is complete.
For long service life and safe charging, lithium batteries need chargers specially designed for charging.
Usually, you also need a system to keep the levels of each unit equal, a process called balance.
Same as for LiCO and lithium polymer packs.
Fortunately, the price of fully integrated chargers has dropped significantly since 2007/2008, with increased accessibilitybalancers.
R/C Hobbymultichargers with integrated balancersI use the term \"multicharger\" just to refer to chargers that can charge and manage most battery chemicals.
These are the most common and cheapest types so far.
The fee depends on how much Li battery you charge. The cheapest (
Such as this thing)
It is usually possible to charge 6 batteries in series, and the charging rate of the battery is limited by 60 watts of power6 cells (22. 2v)
Indicates the charging rate of about 3 amps instead of the maximum 6 amps. High voltage (10S capable)
The charger is much more expensive.
I have IMAX 1010b, very satisfied (
This is my main machine and vehicle charger)
But the price is very expensive.
The new 3010B seems to have the same functionality, but has more power dumping capabilities.
They all need a 10-18 volt (12 is usual)
Power supply as input, which may increase the cost depending on what you already own or want to buy.
These chargers can be set on the battery settings that you use the most.
They will then keep that setting after the power cycle-
So what really needs to happen is plug it in.
They built it.
In the balancer and cell voltage monitor.
In general, getting a bunch of these seems to be the most economical option because the solution is --in-
One, or allin-
If you have a complex electrical system.
If you get an isolated 12 volt power supply for each small charger, you can charge it directly in series output, especially with strange battery configurations.
I\'m making a 4-
Channel series charger for quad rotor project.
Supply must be isolated (
Please note how I isolated the word
So as soon as the charger is plugged in, it will not interfere or destroy each other! Another multi-
The channel multi-charger project is recorded in the Jedboard blog.
Special Order
There are voltage chargers with off-board BMS or balancerver there are a lot of battery factories that can sell you a dedicated single-
Voltage charger, my forever \"black screen\" example
Here is the choice of battery supplier BatterySpace.
They are really not much cheaper than the R/C chargers and you will lose the flexibility to change the number of batteries and the integrated balance, but they are 1.
Plug in the power supply directly and 2.
This may be the only option if your battery count is very high, like 12 to 14 seconds and you want a proper charging rate.
Or, 3.
You know this is the only battery configuration you will use.
Except for the nameless devotees.
The current LED flag Driver Power supply has been pressed for battery charging task.
They are small CC/CV power supplies in the box
Led current-
Mode devices, which limit the current to the maximum and allow the voltage to swing to the preset point.
When the voltage is reached, the allowable current is gradually reduced and changed.
If that sounds like the way you charge a lithium battery, that\'s because it is.
MeanWell PLC and HLG-
MIT has explored a range of ways to use as a battery charger.
If your battery is close to one of the available voltages, Cesar Electronics is one of the reliable suppliers.
You need an external BMS or at least one unit monitor.
A neat little device is called CellLog 8 m (
Data records don\'t actually seem to be supported)
You plug it into the balance port on the battery and it will monitor the voltage on a single battery
If there is any lithium battery threshold that exceeds or falls below the preset, please remind you with annoying buzz.
At least, this tells you to stop charging.
There are quite a few \"kit\" BMS systems for electric vehicles.
I can\'t say I used to screw up with any of them because I always use the first route.
The \"MiniBMS\" project is an example developed by several members of the electric vehicle Forum.
Special Order
Be aware that balance is not an activity that you often perform.
Cheap R/C devices and batteries are more common, as these batteries do not usually match until they are assembled into packaging, because QC steps take a long time (
Read: spend a lot of money)
Most users will be balanced.
Multi-charger enabled.
However, if you are running A123 batteries, mittecicscooterflock finds them reliable and good
Match enough so that balance is just what you do every few weeks and months;
Then, only after checking the battery voltage will it be known if this is worth it.
For example, on melon
Scooter, I take the battery out every semester to check the battery voltage.
In general, if the packaging is good
First balance (
This is very helpful with a multi charger)
The distance between cells is not too far.
I have always been 0.
There is a 02 V or better voltage match for each check, but I still threw them on my charger because it is there.
Using a manual balancing system, the entire package is charged before the constant voltage level cut-offi. e.
The final charging voltage has been reached and the current has gradually decreased.
The whole package is removed from the charger and settlement is allowed.
Then, either low battery charge-by-
One is used to match the rest of the package, or to drain high batteries using a power resistor load to match other batteries.
So at this point, I have introduced most of the major electrical components of small electric vehicles.
I have basically listed how to adjust the size of the motor, which are my favorite and which controllers (
School of control)
Use, how to make sure you don\'t start a battery fire, and maybe make Hobbyking very nervous right now.
I don\'t care because in the past year or more I splurge money there at least once a month.
I think they should pay for it.
The rest is tips I found to help assemble random links to electrical systems and other things.
Do not use the cheap radio rocker switch as the main power switch.
Get a real high
Current key switch or similar switch (
The Hella key switch and its huge red knob cousin are very popular).
Cheap rocker switches will soon be eroded by electricity
Unless you have a pre-charging circuit or an influx restriction (
Both search terms are helpful).
Also, although the switch looks as strong and metal as Figure 2, the contacts inside are still small and can only pass through