EXTENDING YOUR RV BATTERY LIFE
Just like the batteries in every battery-operated you have, your RV lead-acid battery – 12-volt or 6-volt – is what you’d have to call a consumable good. Yes it’s rechargeable, but even rechargeable batteries have a life-span. The good news is, by understanding a few simple facts and developing a few simple habits, you can extend you RV battery lifespan.
Unlike an alternator or generator, a battery doesn’t create electricity – it simply stores it. It’s not accurate, but think of it like a container of water. As you use the electricity, the container drains. A generator or charger can replace whatever was used to make the container full again. This draining and refilling is called a cycle. A cycle can be a partial draining and complete refilling, a complete draining and partial refilling, and anything in between.
For a rechargeable battery, which is what your RV has, the cycles are made up of discharges and recharges instead of draining and filling.
The lifespan of your RV battery depends on how deep the battery is cycled when it’s used. Starting with a 100% charged battery, discharging it to 15%, and then recharging it back to 100% would be a deep cycle. If you begin with a 100% charge, discharge to 90%, and then recharge it back to 100%, that would be a shallow cycle.
Now think of the cycles as wear and tear, or even mileage, for your RV battery. The shallower the cycle, the less wear and tear. The math isn’t exact, but a battery that never gets discharged below 50% will last approximately twice as long as a battery – or bank of batteries – that’s been deep-cycled on a regular basis. Anything above 50% is best, but some experts will say that 40% is acceptable.
So, the biggest tip, is to avoid discharging your RV battery more than necessary, and recharge it as full as possible as soon as possible.
To keep track of how much charge your battery currently has, you can use the following chart that relates voltage to capacity under a light load.