I'm looking into upgrading my solar well pump kit, which is set up for gel lead acid batteries in a 48v system. The kit comes with its own solar charge controller, but it isn't compatible with lithium batteries. To use lithium, I'd have to invest in a separate charge controller and rewire things to connect it to the battery bank. My current gel batteries are struggling after a harsh winter at my cabin, and I'm considering moving to lithium for better efficiency. I already have 8 panels of 100 watts installed and planning to add 8 more, still keeping everything at 48v. Is it worth the extra cost to switch to lithium and get a new charge controller, or should I just stick with gel batteries?
3 Answers
Definitely consider the separate charge controller if you switch to lithium! The initial investment will pay off in efficiency. I mean, those lithium batteries perform better, especially in colder conditions where gel leads might struggle. Just make sure to set it up correctly with cutoff points to protect your investment.
It's a bit tricky! If your pump kit includes a charge controller but can't handle lithium batteries, you definitely need a proper MPPT charge controller to manage those lithiums. Trust me, it's worth it for the efficiency you get from lithium! You'll likely get better performance overall compared to hanging onto those gel batteries that might not last much longer in your situation.
From what I gather, as long as you pick a good charge controller with adjustable settings for maximum voltage and safety cutoffs, you should be fine using lithium batteries. I've gone through this setup before using standalone MPPT solutions, and it can work without any major issues. Just keep in mind you might not get the full power range from the batteries, which could impact their lifespan.