If you’ve ever found yourself running RC packs all day and wondering how to recharge them without access to an outlet, this field charging RC LiFePO4 setup might be exactly what you need. In this post, I’ll walk through how I recharge my 8S CNHL G+ packs in the middle of nowhere using a 100Ah LiFePO4 battery.
You can check out the full video linked below for the second half, where I take the Limitless V1 for a few high-speed passes once the packs are topped off.
Setting Up the Field Charging Station
After running a few packs through the Limitless V1, I was completely off-grid — no power outlets, just trees all around. To keep things going, I rely on a 12.8V 100Ah LiFePO4 battery setup in my vehicle’s trunk. You could also set this up on the ground outside the vehicle as this will be safer. It’s powerful enough to charge multiple 6S or 8S packs several times a day.
The setup is straightforward. The LiFePO4 battery connects directly to my dual-channel charger. From there, I can charge two packs at once, typically around 10 amps per channel, which equals a 2C rate for 5000 mAh batteries.
Charging Performance
Once everything’s plugged in, the charger boots up and begins ramping up the charging current. Each channel starts delivering steady power at 10 A, bringing the packs from around 3.9 V per cell back up to full in under 30 minutes.
During one of my recent sessions, the system drew over 50 A from the 12 V LiFePO4 source — no problem at all thanks to its 100Ah capacity. That’s the big advantage here: plenty of current delivery for multiple recharges in one day without worrying about draining the power source. But also, the ability to charge very aggressive as 50 A from a 12V source is 600W of charging power.
When it’s time to recharge the LiFePO4 itself, I use a 14.6 V LiFePO4-specific charger, which tops the big pack off safely at 30 A in about two hours depending on state of charge. It’s fast, efficient, and ready for another full day of speed testing.
Why This Setup Works So Well
Compared to older deep-cycle batteries, this field charging RC LiFePO4 setup offers a huge improvement. My previous deep-cycle battery could only handle about 12 A of charging current back into it. This 12.8 V LiFePO4 comfortably supports 30 A or more. Also, a 100Ah deep cycle would not provide a useable capacity of this amount. We see this all the time with our LiPo RC batteries for RC vehciles. However, the 12.8 V LiFePO4 has an increased useable capacity. You will get nearly all of that 100Ah capacity out of the battery for charging power! That means faster turnaround times, higher efficiency, and consistent power even when charging multiple 8S packs at once. Perfect!
Want to See the Speed Runs?
After charging, I took the Limitless V1 back out for a few road-course-style runs. If you want to see how it performed and what speeds I hit on 8S power, check out the full video linked in the post — it’s worth watching.