12V to 85V Buck Boost Regulator Needed

[Ubergeek63]

unless they are in discontinous mode... the peak then is higher than the 42A. very few controlers can handle operation at the crossover point.

Dan

 

[mneary]

k7elp60 Has the seed of a great idea! Get a small inverter with a capacity of maybe 240W. This usually consists of a simple regulated 12V to 165V boost or flyback converter connected to an H-bridge that makes the 50/60 Hz.

Tear out the H-bridge and change the regulation to 85V instead of 165.

 

[Hero999]

I do not want to do that because if one battery drains, the whole chain fails! even if the rest of the batteries still have plenty of charge on them.

I experienced this issue before with one of the 6V battery being more drained than the other 6V battery in series.

IF you charge the batteries in parallel then this is very unlikely to happen because the batteries will become balanced.

A flyback topology will be much more compact because the duty cycle on the primary can be lower to get the same voltage increase. A autotransformer will give you a small reduction in size and cost.