Hey everyone! I'm totally new to solar energy and I just bought a solar panel, charge controller, and inverter setup. The specs are: a 100W, 12V solar panel; a 7A charge controller; and a 300W inverter that converts 12V DC to 110V AC.
I'm currently looking for a 12V battery but I'm a bit lost with all the technical jargon. Can I use any 12V battery, like the ones for cars? Are there specific batteries that are better for solar energy storage? I found an MK brand SLA battery that's 12V, 7.2A, which seems to match my setup. They've got other options too, like 10, 12, 18, 22, and 33Ah. What's the difference between Ah and A? Is there a beginner-friendly guide to help me understand all this better? Am I even understanding these specs right?
Thanks for your help!
4 Answers
Skip the sealed lead-acid batteries. I’d go straight for a 100Ah lithium LiFePo4—they’re really affordable on sites like Amazon and great for your needs!
Great question! The Ah (amp-hour) rating indicates how much power the battery can store, while A (amps) is the current. Yes, you can use typical lead-acid batteries as long as your charge controller supports them. Just keep in mind that car batteries discharge quickly (good for starting engines) and aren't ideal for slower, deeper discharges that solar systems often use. For solar, deep cycle batteries are better. Remember: 12V × Ah gives you total watt-hours. So for instance, a 33Ah battery would support a 300W inverter for a little over an hour, but only if the inverter is running at full capacity, so watch out for that! You should also look into the specs of your charge controller since different batteries require different charge methods. And if you're confused, definitely check out some YouTube channels like Will Prowse for more info and insights!
Yeah, I'd avoid SLA batteries if you can. They’re not the best for solar since they don’t handle deep discharging well. Deep cycle lead-acid batteries are generally more cost-effective for what you're trying to do. Also, I wouldn’t recommend lithium batteries with your current charge controller setup just yet; stick with something simpler until you’re more familiar.
If I were you, I'd recommend looking into LiFePo4 (Lithium Iron Phosphate) batteries. They’re generally more efficient for solar applications compared to SLA batteries, even though they might seem pricier at first. This video covers a lot about battery types and solar setups—definitely worth a watch: [https://www.youtube.com/watch?v=t3Ubx-M0nXU&t=216s](https://www.youtube.com/watch?v=t3Ubx-M0nXU&t=216s). A 100Ah LiFePo4 battery would give you a solid start!
Thanks for the detailed breakdown! I’m definitely going to check out those channels for more clarity.