>> the fastest chargers lower their delivery rate ( - I suppose the car must be in control of it - ) once the %age full gets over 80%, to protect the batteries, so it becomes much slower but presumably that takes less power.
I literally meant efficiency - (kWh in)/(kWh out). Not speed.
We once had a boat with a BMS, that basically told us how many amp hours were left in the 12V (lead acid) battery bank. It did this by measuring power in and power out. There was a setting for charging efficiency, we used 90% which seemed about right.
|