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#### brian_

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EV West's web site can be a really convenient source of quick specifications, and you might even choose to purchase from them some day, but in most cases (including this one) more detailed and authoritative information is available from the company which actually makes the products. In the case of this motor and inverter is Cascadia Motion.

#### brian_

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Now, The AM Racing Motor has a Max Voltage Input of 360V and a max current of 600 arms(I have no clue what this means).
That's supposed to be "ARMS", meaning "A" for amps (the measure of current) and a subscript "RMS" for "root mean squared", meaning the type of average value used for sine waves. It's the way you need to consider current if you are using that current value to calculate power - the same applies to voltage. Often specs will just say "A" for amps and assume that you know it means the RMS version when it is an AC current.

The LG Chem Super Cells have 1.6 kWh of storage and 63 amp hours of capacity(no clue either)
1.6 kWh is the amount of energy stored by the module. In electricity, power is current multiplied by voltage, and energy is charge (product of current and time) multiplied by voltage. So this module can produce 63 Ah (amp-hours) of charge output, which could be 63 amps for one hour, 126 amps for half an hour, 21 amps for three hours, etc.

They don't really need to provide both of these specifications if they are also providing the nominal voltage. If you have any two of nominal voltage, amp-hour charge capacity, and energy capacity, you can calculate the other one. For instance, they say that this module has a nominal voltage of 25.55 V, so
• energy capacity = 25.55 V * 63 Ah = 1600 Wh or 1.6 kWh
• nominal voltage = 1.6 kWh or 1600 Wh / 63 Ah = 25.55 V
• charge capacity = 1.6 kWh or 1600 Wh / 25.55 V = 63 Ah

#### brian_

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Doing the math from a previous post explaining how to size up your battery (Sizing your Battery Pack), I got:
350 Wh/mile x 80 miles= 28 kWh
Therefore, would it be correct to assume that I need 28 kWh from my batteries to reach this range?
Yes.

So with my battery packs, I would have to chain them in series until I reached 28 kWh? 28/1.6=17.5 battery packs
You would need that many modules ("packs" usually means something a little different), but how they're connected doesn't change the energy capacity.

However, the article does mention that this process was applied to a 120-volt system. How does the 360V motor change this, if at all?
It doesn't change the required energy; the motor needed to operate the motor properly determines how the battery needs to be configured, not how much total battery is needed.

Then, 28 kWh/360V= 77.78 Ah x 1.32= 102.67 Ah
Now, this is where I can't follow anymore. What does the amp-hour requirement mean? How does it apply to my battery and my motor requirements? Would I have to place my batteries into parallel until I achieved this value?
What's the factor of 1.32 for - are you converting 360 VRMS of motor current to DC battery current?
Yes, if your battery is to have 28 kWh of energy capacity and 360 V nominal voltage, it would have 78 Ah of charge capacity.

What about with the motor? It has a max draw of 360V and I have no clue about the current.
A motor doesn't draw voltage. It gets whatever voltage the controller gives it. The voltage specified for a motor is usually the voltage that it need to deliver the stated power output at the stated speed. At low speed the controller will give it much lower voltage; the controller can put out less voltage (and proportionately more current) than it gets from the battery, as required to operate the motor as desired.

The stated motor current will be a maximum - more than that and it gets too hot. That same amount of current will be required to produce the maximum rated torque - torque is basically proportional to motor current.

If I wanted to power this motor, I would realistically need at least 360 volts from my batteries. Then I would have to chain my batteries in series to achieve the correct voltage, correct?
If so, 360V/25.55V=14.1 battery packs.
If you want to get the full rated performance over the expected speed range, then yes you need that voltage. Yes, you connect modules in series to reach that voltage, since the controller can only reduce voltage from the battery, not increase it.

How do these all connect to one another and how do I ensure that my battery choice will match the power draw required by my motor?
Power is something that you haven't addressed at all before this. With a large enough battery to get the desired range, it's usually large enough to handle the power demand, although an unusually high-power motor and a battery capacity chosen for short range can combine to result in a battery that can't handle the power requirement.

In this example, the motor is apparently capable of 210 hp peak output, which is 157 kW. Due to motor and controller inefficiency you might need 170 kW. If you had 17 of the linked modules providing 500 amps (which is what the EV West spec claims they can do), that would be 17 times 25.55 volts times 500 amps which is 217 kW... more than enough.

The other way to look at power requirement is to compare it to energy capacity: a 28 kWh pack could deliver 170 kW for 1/6th of an hour before running out... if it could handle that rate of discharge. That's called "6C" (six times the battery capacity per hour), which is substantial but probably manageable (briefly) for typical EV modules.

#### brian_

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However I did want to ask that since the motor will accept whatever voltage it gets, that means that having a lower voltage available from the battery won’t necessarily cause trouble right? It’ll just have less performance.
Right - lower battery voltage will only affect performance at higher motor speed, where more voltage is required (for the same current and torque) to overcome back-EMF.

What about with amp hours? If I don’t meet the amp hours that I calculated, that would simply mean that my range is reduced compared to what I wanted, correct?
Correct... except that if you make the battery small enough in energy capacity it may also have insufficient power capability for peak power demands.

The 1.32 was to account for the peukert effect and not wanting to drain the battery fully (80%).

There's not much peukert effect with lithium-ion, but allowing for a reserve makes perfect sense. In published specs for EVs you'll often see "nominal" and a substantially smaller "usable" battery capacity for this reason.

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