By Dave Solberg
Dear Dave,
I’m looking for a meter that will indicate the remaining charge in my lithium battery. I picked one up that said it would work but it always reads 100%, even after a couple of days of use. Any suggestions? 2019 Wolf Pup 16FQ, with an updated charge controller for lithium batteries. Thank you. —Ray, 2019 Wolf Pup 16FQ
Dear Ray,
It seems like everyone is getting into the battery management circus with products popping up everywhere. Same thing with lithium batteries and cheap monitors. I have installed the Expion360 Battery Monitor as well as the Go Power! Battery Management Kit and both have been outstanding.
The first was a few years ago when we installed a new set of Expion 360 100 Ah lithium batteries in the 2016 Thor Challenger. The existing battery indicator was the standard light bar that everyone used inside and was not accurate at all. It was an easy install, and the owner is still very happy with it.
Go Power! GP-BMG Battery Manager Kit
Just recently we installed the Go Power! GP-BMG Battery Manager Kit on our ’96 Salem trailer on a trial basis to see how well it works with a single Flooded Lead Acid (FLA) battery, and it has worked well. The only problem is the battery is very cheap (box store cheap) and it drains down fast! We will be installing another unit on a 2016 Renegade RV IKON that has a huge AGM battery bank, so it will be a better test.
What I like about the Go Power! kit is the easy installation and friendly monitor panel.
It will not only tell you the percent of charge, but also the time left at current draw rate. That way, if something else cycles on, you can see the difference rather than just the charge state. And it is Bluetooth compatible. The shunt is mounted directly to the negative battery connection and then you set it up to the type of battery, voltage, and capacity (Ah).
You can find it at most RV dealers or on Amazon here.
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Got lithium batteries with used coach; they’re dead. BMS Bluetooth doesn’t work. Now what?
Dear Dave,
I bought this camper used; I’m the second owner. It came with these batteries. Original owner told me they were lithium. My question is, what is or are the extra pieces with the batteries? Went to one RV dealer and asked; he said he didn’t know. I didn’t get any paperwork on the batteries. Thanks. —Ed, 2016 Coleman Lantern
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RVDT2754
I have a feeling Ray either didn’t program his battery monitor with the proper reserve capacity.
My shunt style battery monitor required me to tell it my amp hour capacity so that it could calculate the percentage remaining off voltage drop. If Ray has 400 amp hours of reserve but left the monitor set at 100, it’ll take forever for it to get off 100%.
My monitor also allows for “fine tuning” the voltages since Lithium battery voltage doesn’t drop like wet cells do as it discharges. The Bluetooth feature is cool too as it allows me to check battery status in real time anywhere around my RV versus having to stand in front of the monitor screen.
The SFK batteries I use have Bluetooth and a battery monitoring phone app that provides all the information I need. Many other lithium batteries have similar capability.