lead acid to lithium battery swap

[youngbuckwithapickuptruck]

i vanlife and charge a lot of my stuff off my lead acid battery and killed another one after only three years. i was suggested replacing with a lithium ion battery, as they are now cheaper than lead acid.

the only caveat is that they require a Battery Management System. are the LiO batteries with the bms cheaper?

 

[pentode]

I don't want to sound negative but I would be very careful with batteries like that for a few reasons. I don't think automotive lithium tech has advanced far enough that a safe lithium car battery will be cheaper than lead acid.

I helped a friend spec out a marine system and I found troubling inconsistencies between sales brochures and data sheets. The battery my friend wanted to use bragged about having a "built in BMS for safety" but when you dug through the tech specs it required an (expensive) external regulator to protect the battery. When he contacted their sales they said "no, the alternator regulator isn't enough, it needs very stable power for charging". And this wasn't cheap Amazon stuff, it was quality marine -grade gear.

Just be really certain of what you're buying and I'd say resist the temptation to go too low on price with lithium - there's just too much dangerous junk out there IMHO. If you need durability that's definitely compatible with vehicle 12v systems, consider an AGM or deep cycle battery depending on your exact use case. Yeah, they're not super cheap but they'll survive deep discharges much better than normal starter batteries.

 

[lil_Blue_Ford]

Yeah, deep cycle batteries are what you need for constant discharge/recharge. Also, no automotive batteries seem to last very long anymore. It’s becoming a problem.

As for cheap Lithium batteries, I’ve seen where people have cut them open to find nothing but rows and rows of cheap like 18650 batteries linked together.