Let’s face it, since us Toy Hauler owners mostly dry camp, our batteries are extremely important. Following are some tips I’ve picked up over the years along with some products I think are worth a look.

The life of your deep cycle batteries will largely be affected by how it’s used and how it’s maintained.

How it’s used
How a battery is used is probably the single most important factor on how long a battery will last. This is typically measured in the number of deep discharges and the average depth of each discharge. A golf cart style battery like the Trojan T-105 will last for about 750 discharge cycles if the average depth of discharge is at 50% of its capacity. But if the depth of discharge increases to 80%, the number of cycles drops to only 225.

Most experts agree that you don’t want to let your battery’s state of charge get below 50%. So looking at the following chart you don’t want to let your batteries get below 12.06 volts and never under any circumstances let it get to 10.5 volts. Doing so, could damage your batteries.

To measure the depth of discharge and other important metrics like current voltage, consumed amp hours, and time remaining, you may want to invest in a good digital battery monitor like the LinkPRO from Xantrex. The LinkPro can also be programmed to automatically start your generator when your batteries get to a pre-set limit.

How it’s maintained
Good battery maintenance includes making sure the water level never gets below the top of the lead plates. Since battery compartments are dark and usually cramped, I found the best way to accomplish this is to get an automatic watering system like the Pro-Fill system by Flow-Rite.

The Pro-Fill will take you about 5 minutes to install and is made of top quality parts. Once hooked up all you need to do is pump distilled water from a jug with the included hand pump. No more need to remove the vent covers and make a mess.

For a complete review of the Pro-Fill, click here

Besides water, proper charging of your battery bank is very important. Keeping them charged using a quality intelligent 3 stage charger will accomplish this. I’ve had good luck with the Converter/Charger from Progressive Dynamics. PD’s 9200 series chargers when combined with their Charge Wizard constantly monitors your batteries voltage and selects the proper mode to safely charge your battery.

It’s also important to recharge your batteries as soon as possible after discharge. Batteries don’t like to sit depleted for long periods of time. And during storage, if possible, keep your rig plugged in so your batteries don’t waste a discharge cycle. Otherwise remove your batteries, take them home, and put them on a trickle charger.

The Effects of Temperature
Battery capacity is reduced as temperature goes down and increased as temperatures go up. At freezing, capacity is reduced by 20%. At -22F capacity drops by 50%. When temperatures reach 122F battery capacity increases by about 12%, however battery life is shortened. Therefore, extreme temperatures in either direction are not good for your batteries health. Charging times are also affected by extreme temperatures. This is why most intelligent chargers will have temperature compensation circuitry built in.

Summary of Key Points
• Try not to go below 50% of your batteries rated capacity
• Never let your batteries get below 10.5 volts
• Keep your electrolyte levels above the lead plates
• When at home, keep your batteries charged 24X7
• Recharge soon after depletion
• Charge your batteries using a quality intelligent charger

If you follow the above tips you will maximize the life of your deep cycle batteries.