48v charging

[Steve Herrera]

I have a 48V mid drive bike, any way to charge the battery with a 12 automotive battery? (panasonic 48v)

[ykick]

No elegant way.

You can use some automotive AC inverters from the 12VDC battery powering the AC wall charger.

There's also DC-DC "buck converters" but they're awfully inefficient and easy to screw-up adjusting for that amount of DC voltage conversion.