Preface
Battery packs and the cells within them are one of the most crucial and complicated parts of any EV build. From Tesla to DIY golf cart conversions, battery cells are at the core. Choosing the correct cell for any application can make or break any EV build before its complete. This post goes into the details of the specific cell chosen for the eCaddy battery pack.
Ampace JP40 21700 Cell
The eCaddy is going to need a huge amount of power on demand. Upwards of 2000 amps to be exact. Currently there are not very many cells on the market that can keep up with that kind of tasking. Below are some of the quick specs:
- 60 amp continuous discharge
- 140 amp burst
- 4000 mah capacity
Diving deeper into theory
With the eCaddy battery there are really two areas we care about the most.
- Amperage (continuous/peak)
- Voltage
- Capacity
Amperage
This is one of the most important aspects of any battery pack simply because it is so easy to get wrong. There are countless way to build a battery pack, however if your load is going to pull too much than the battery can provide bad thing will happen. This includes lack of performance, overheating, fire, etc.
To solve this any build needs to choose the correct cell and configuration from the start.
Voltage
Most EV's on the market today run on 400 volts. Of course there is also the up and coming 800 volts architecture which is used by manufactures such as Porsche. But since the eCaddy will be using Tesla drive units we will be building for 400 volts.
We can easily get to 400 volts by using a series connection like any other manufacturer. We will be running a 96s configuration for the eCaddy battery pack.