As of this writing Off Grid Trailers ship with 2×100 Amp Hour (Ah) Canada Proof lead acid batteries. The reason is because the Off Grid Trailer company is based in Edmond Canada and they camp in subzero temperatures, and for them lead acid makes a lot of sense but if you hate the cold then the batteries need an upgrade.
The biggest problem with lead acid
Lead acid batteries shouldn’t drop below 50% or you can damage them so 200Ah it tuns into 100Ah. Lead acid also need constant charging (trickle charge) they will just go dead if not constantly charged. Lead acid car batteries are also designed for short burst of high power (such as starting a car). I just didn’t feel lead acids were going to be enough for what I needed. I also wanted the ability to monitor the battery and see the exact charging/discharging status. My desire to know exact battery status came from the first trip with the Pando, it was freezing and my batteries where at 12.3 volts and I had no idea if I should turn on the heater or not. The Lithium upgrade and monitor lets me know exactly how much power I have and how much I am using and unlike lead acid I can consume more than 50% power without damage.
Which brands to go with?
Battle Born seems like a very reputable brand but are a little pricy and their web site is hard to use. SOK has a slightly larger than standard sized battery that puts out 206Ah but cost well over $1,000 each and they are Chinese. Renogy has 100Ah Smart Lithium Iron Phosphate Battery w/ Self-Heating and Bluetooth that are just a little smaller than the standard battery size. The Renogy batteries retail for around $680 but Walmart.com had them for $450 each. I ordered two Renogy Smart Lithium-Iron Phosphate Battery 12V 100Ah w/Self-Heating Function and one Renogy Bluetooth Module all for under $1,000. The downside of lithium is the chemical reaction doesn’t work below freezing, to compensate the heating starts at 40 degrees and turns off at 50 degrees (which does take a slight drain on the battery in cold conditions). I went with the Renogy brand because they seemed reputable were affordable and I like the way the batteries linked together and communicated through a single Bluetooth module. A note on the connections you will need a short CAT5 cable to link the batteries then you can connect 1 Bluetooth module or 1 battery shunt but not both.
Steps of the upgrade
To get to the batteries you should remove the lower shelf, to get to the lower shelf you need to remove the upper shelf, and to remove the upper shelf you need to remove the spare tire holder. After the tear down to the batteries it’s pretty simple.
- Unplug the trailer from shore power
- Trip the circuit breaker
- Unplug the Ground / Negative first on the batteries
- Unplug the positive side
- Remove the lead acid batteries (they are heavy)
- Modify the Battery bracket to hold the new smaller batteries
- Wire the batteries in parallel (positive first)
- Wire the batteries in parallel (negative / ground last)
- On Battery 1 put CAT-5 cable in Link-port
- On Battery 2 put CAT-5 cable from Battery 1 link-port to Battery 2 Up-Port
- Plug in “Renogy on/off” cord into Battery 1 “Up-Port” and turn on
- Unplug “on/off” cord (store it in Pando onboard tool kit)
- Battery 1 plug in Bluetooth monitor into Up-Port
- Download App to phone and pair Bluetooth to batteries via app (not phone settings)
- Go to Xantrex setting and enter custom settings.
You will then need to reassemble all the brackets and shelfs back together – don’t forget to use the Sikaflex 221 on any exterior bolts.
Check out these videos for more details:
Setting up the batteris:
Renogy 12V 100Ah Smart Lithium Iron Phosphate Battery – YouTube
Setting up the Xantrex to use lithium.
How to Set Your Inverter/Charger for Lithium Ion Batteries FT: Full Moon Adventure Club – YouTube
The settings I used for Zantrex custom settings:
- 20 -> use
- 21 -> skip (hot)
- 22 -> 14.4
- 23 -> 13.2
- 24 -> 50 amp *** on 6/10/2023 changed this to 20 amps to get ALP generator to run in ECO Mode.
A note on setting #24 max amps for charging. The more the amps the faster the charging and the hotter the batteries can get. The Renogy batteries I have are a specification of 50 amp so I used 50am instead of 80amp mentioned in the video. Now when your charging 2 batteries in parallel it will split the 50 amps between the two batteries or about 25 amps each. However, if one battery happens to charge to completion first then when it hits 100% that means the remaining battery will get full 50 amps. When the batteries ship, they will not be at the same exact Ah and it could take several charging and discharging sessions before they start charging evenly, and at that time I might bump it up to 80 but probably won’t. Note: if you need to charge from the inverter built in your car you will probably need to drop the amps way down (again only emergency situations would call for that).
The App
The app shows the summery on the front page (Max capacity, present capacity, and remaining time) There is also information for each battery:
- Battery level
- total max capacity
- present capacity
- present voltage
- present current
- if heating is on
- Average temperature (inside the battery)
- Individual cell voltage
Based on the app here is the usage (average based over multiple samples)
| Battery Usage | current |
| Camper at resting state (power going to USB ports and carbon monoxide detector) | -.0280 |
| Furnace Heating & Fan (heater does not run constantly) | -2.217 |
| Furnace post heat cycle (furnace fan only for few minutes) | -1.225 |
| Front Box and Rock Lights (5 LED lights) | -0.88 |
| Maxxfan Deluxe 7500 Fan 50% | -1.13 |
| Maxxfan Deluxe 7500 Fan 100% | -3.0 |
| Dometic 57L Fridge (the compressor does not run constantly) | -4.64 |
