The One Good Road

What is a Battery Monitor? Why Do I Need One? If you're building a DIY off-grid solar system (or already have one), you've probably run into this situation, you've got your lithium or lead-acid batteries set up, your inverter and charge controller wired in, but you have no reliable way to know how much battery capacity you actually have left. That’s where a battery monitor with a shunt comes in. Most batteries don’t include a built-in monitor, which leaves you guessing based on voltage alone (a method that's not particularly accurate with LiFePO4 batteries) how much capacity you have left. Whether you're using a single 12V battery or a more complex setup, installing a shunt-based monitor gives you real-time insight into your system’s performance and helps you get the most out of your energy storage. There are also other systems worth considering, like hall sensors (similar to a clamp meters), to measure how much current is coming in and out of the battery, but long ...