I am trying to get info on building a high voltage hybrid car NiMH battery charger.

They are based on 28 cells of 7.2 volt/6.5Ah in series resulting in a 201,6 volts (much higher when charged).

One idea is to seperate the battery cells and make 28 discreate chargers but this leads to higher cost.

The other idea is to have one high voltage charger of about 300 Volts max at 0.1-0.2C with timer and voltage circuits to monitor the process.

Any ideas welcome,

Ioannis