# Calculate the charging time for my Electric Vehicle

• Lobotomy

#### Lobotomy

So cars usually specify the batteries in kWh (rather than Ah).

So given that i know the kWh capacity of a car.

I also know the charging effect in W (i.e. the voltage and amps in my charging station).

Can I reasonably estimate the time it'll take to charge the battery? It doesn't have to be super accurate.

Is it as easy as

Capacity / Charge effect = time i.e.

100kWh / 9600 W = 10,4 hours to charge?

And assuming i have 5 hours to charge that'll reguire 100kWh/5= 20 000W if i want to be able to charge it full in that time.

To account for various inefficiencies, especially of the batteries, add about 20% to the amount needed for full charge. The faster the charge rate the less efficient it is. Also the faster the charge rate the sooner the batteries will need replacement due to loss of capacity.

To account for various inefficiencies, especially of the batteries, add about 20% to the amount needed for full charge. The faster the charge rate the less efficient it is. Also the faster the charge rate the sooner the batteries will need replacement due to loss of capacity.

add 20% to time or effect?

add 20% to time or effect?
Isn't it saying the same thing either way?

In the "Real World", add to the the time if longer battery lifetime is important to you. If you are impatient, add it to effect.

It's just a case of batteries not being 100% efficient.

100kWh / 9600 W = 10,4 hours
10.4 hours plus 20% = About 12 hours.