How Long Do Solar Batteries Last When Used While Charging?

So, about battery lifespan while using and charging: it can really depend on the battery type and how you use it. For off-grid setups, getting around 10 years is pretty common if you treat your batteries well. As for using a battery while charging, it's more about how your system is set up—when they're designed right, you can sort of use both simultaneously. Just make sure your solar input can cover your load plus charge the battery. Regarding battery switching, it's best to have both batteries in a single bank rather than trying to switch between them. Keeping them combined helps maintain good performance and prolong their life.

To clarify about simultaneous use: if you're using a battery while it's charging from solar, you're not actually drawing from the battery at that moment—you're pulling directly from the solar input. This means less wear on the battery. As for that automatic switching feature you mentioned, you'd generally set up an inverter with different outputs for critical and standard loads instead of neatly switching batteries.

When it comes to battery lifespan, it really hinges on the battery chemistry and keeping it in the sweet spot of 60% charge. If you're running both batteries together, make sure they're identical so they wear evenly. As for going back and forth between the batteries—most systems advise integrating them into one battery bank rather than using them separately. This means you'll avoid complications and get better efficiency.