I have a 48v 12Ah lithium battery pack, and I want to connect one or two lead-acid batteries of 12v 12Ah to it to make it 60v or 72v 12Ah. I can charge it with a 60v or 72v lithium charger. Will this setup work????
i give it a go and it worked like a pro. For few minutes, it worked alright. I will test it for longer use
Generally it’s a very bad idea due to different discharge curves for different chemistries plus the increased problems with series connection of any batteries. If you do manage to have floating or differential undervoltage protection and balance charging, you could make it work. However, if you need to ask, I would determine you don’t have the skills to make this happen and understand the underlying difficulties. If it’s just for a single bench test, you will get your 60 V but as a connect and forget charging solution, it’s a recepie for disaster when the cells become unbalanced eventually.
So no.
I can charge it with a 60v or 72v lithium charger.
No you can't.
Lithium and lead-acid chemistries require entirely different charge procedures. Attempting to charge a series lithium/lead-acid combination by pretending it's a lithium battery will damage one or the other (probably the lead-acid, but Murphy's Law says the more expensive lithium).
For charging your proposed setup you need separate chargers for the two batteries.
