Battery

As we all already now that batteries main problem is that they tend to discharge too fast. There's never not enough energy. But technology electronics and maschines tend to develop and use more and more power seems like batteries are just a little bit lag behind in development, but it makes all the difference. Battery changes electric energy into chemical energy and stores it until someone connects a load to it and then it starts to change stored chemical energy into electricity on its plus and minus terminals. Batteries use to be measured in amphours Ah it meant how many amperes in one hour you could get from the battery. Its ok to use it on a usual ICE car starter battery because they mainly are 12Volt batteries. On electric cars its not very often so, only BMW is using this at the moment (2020) on their only EV BMW i3. They offer 120Ah battery for the car by the way when they started to sell this model (in 2013) it had half the capacity 60Ah. In a few years batteries have gone twice as better! 60Ah is 22kWh and 120Ah battery is 42kWh. To describe batteries on EV-s is mainly in use unit kWh kilo Watt hour. This is unit for measuring electric energy and it fits much better with cars since they use a lot of energy. Kilo Watt hours is also used in home energy consumption. Only difference is that you multiply Volts with Ah and you get Watt hours if there are many of them then you will use prefix kilo.

Theres electrical safety and physical safety. Batteries need to be taken care of not to overcharge and undercharge. Nowadays 400V EV batteries consist of 96 cells connected serially. Each serial cell voltages are monitored that is the job of BMS

Battery monitoring system (BMS) or Nissan names it LBC lithium battery controller. Takes care of battery “health”. EV battery has to last for 10 Years and to fulfill this expectation there is a bunch of electronics and clever software.