Hey everyone, I'm not usually active here, but I could really use some advice. I've got two 200AH 12V batteries connected in parallel (positive to positive, negative to negative), along with a 590W solar panel using an MPPT charge controller rated at 60A and an inverter for power during outages. The issue is that since connecting both batteries, the charging current from the solar panel dropped significantly from around 40A to just 18A. Right now, I'm connecting both positive wires (from the inverter and MPPT) to Battery A and both negative wires to Battery B to try to balance the load. However, I was told by ChatGPT that I should connect both the positive and negative wires to the same battery. I'm afraid this could lead to one battery deteriorating faster than the other. Should I stick to my current setup or switch to connecting the positive wire from the MPPT to Battery A and the inverter to Battery B, with the negatives swapped accordingly? I just want to ensure I'm charging properly without damaging either battery. Thanks for your help! ❤️
2 Answers
Don’t stress too much about the AI advice; machines can't replace human experience! It's also good to remember that the current may naturally drop as your batteries get closer to full charge. Monitor the charging profile over a few days to see how both batteries perform. If they're both getting equally charged by the end of the day, you're probably just fine, but keep an eye on those connections!
It sounds like you're almost there with your battery setup! Generally, when connecting batteries in parallel, it’s best to keep the positive of the charger linked to the first battery and the negative to the last battery. Your current connection might not be a big issue since you’re only using two batteries, but ideally you want to minimize the potential for imbalance. Make sure all your connections are tight and well-torqued to avoid any resistance which could cause the lower current. Using busbars for your connections is also a solid tip — it simplifies things and ensures good contact.
Totally agree! Just make sure those connections are solid to get the most out of your system.
Yeah, just track the voltage on both batteries; if they're syncing up, you're all good!