Lithium iron phosphate (LiFePO4) batteries have become the most common upgrade RV owners ask us about. The appeal is real. You can use most of a lithium battery's rated capacity, compared with roughly half of a lead-acid battery's if you want it to last. They weigh much less, they don't need water, and they hold voltage steady, so the lights don't dim as the battery drains.
But a lithium swap is not just a battery swap. The rest of the RV has to charge it correctly.
What we check before we install
The converter or inverter-charger. Many older RV converters were built for lead-acid and charge at voltages that are too low to fully charge lithium, or have charging stages that don't fit it. Some newer units have a lithium setting. Some need replacing. See converter chargers and lithium.
Solar charge controllers. If you have solar, the controller needs a lithium profile or custom settings.
Alternator charging on motorhomes. Lithium can accept a lot of current. On some motorhomes, connecting a lithium house bank straight to the alternator through the old isolator or solenoid can push the alternator hard. A DC-to-DC charger is often the right answer. We will look at your setup and tell you.
Cold. Most LiFePO4 batteries should not be charged below freezing unless they have built-in heating or low-temperature protection. That rarely matters in South Florida, but it does on the occasional Panhandle or North Florida cold snap, and for owners who travel north.
Space and mounting. Lithium batteries come in many sizes. We make sure they fit, are secured properly and have the right fusing close to the battery.
Which lithium battery?
There are many good brands. Our guides cover several of them: Battle Born, RELiON, Renogy, Lithium RHINO, Epoch and Trojan. We'll talk through what fits your RV, your budget and how you camp. You can also buy your own and have us install it.
Is lithium worth it for you?
If you boondock, run a residential fridge or an inverter for long stretches, or are tired of replacing lead-acid every few Florida summers, lithium often pays off over time. If you are always plugged in at an RV resort, a good AGM battery may be the better value. Read lithium vs AGM vs flooded for the full comparison.
Questions we get about this
Can I put lithium in any RV?
Physically, almost always. Electrically, it depends on what charges the batteries. That is what we check first.
Do I need to replace my converter?
Sometimes. Some converters have a lithium mode or can be adjusted. Others charge too low for lithium. We will tell you which yours is.
Can I mix lithium and lead-acid batteries?
No, not in the same bank. They charge and discharge differently. A house bank should be one chemistry.