What is the most common RV battery solution? Self-built OR Vendor Assembled?

[TedH]

Many solar battery companies are selling 5Kw and larger self-contained battery banks (metal enclosures) with integral BMS, heat/cool management, connections, etc. in a metal case that can be assembled in parallel or in series. Also, many can now be monitored/managed using power management integration solutions from Victron, EPever and others.

What do you run? Are you planning an upgrade/replacement to more modular, vendor-built solutions?

I built my 15.5Kw battery bank around 48, CALB 100ah LFP cells in a 24v configuration (6P8S) with my own cabling, bus bars, hardware, Daly 500amp BMS and a plywood enclosure. My inverter/charger and solar charge controller(s) are Aims and have limited features/functionality. That saves on learning curve but I lose the flexibility to monitor/manage with Victron components. At this time, I use a Victron CCGX with the BMV712 shunt in order to remotely monitor the DC loads from my House systems and the charging/power from solar, shore power (grid) or on-board generator (all indicated as "DC Power" on the VRM app). I can also power the DC system from an Aims charger up to 37.5 DC amps if for some reason, shore power is limited to a single 30 or 50amp feed. My system is stand-alone and does not add power to the grid.

Today, if I were starting fresh, I'd consider three (or more) of the 24v, 5Kw rack mount battery packs from EG4 or equivalent.

My next big upgrade ($$$) will be to keep my CALB battery bank and swap in Victron suite of inverter/chargers, smart solar chargers, shunts and Cerbo GX with monitor. I will also upgrade to six, 490watt Heliene mono panels. The Heliene's are running about $215-220 (new, grade B).

I almost forgot, my solar is a set of 6, 250watt poly panels that, at peak are good for about 60amps. I rarely see peak. Normally, my peak is about 45amps on the clearest days. The panels are mounted flat on my 40' RV roof between the 'escape hatches'.

 

[RV10flyer]

I built a 26ga metal case for my four Eve 105aH 24V batteries in my Chevy Express work van. About 10kWh total. 4 ea REC405’s to keep it them charged and run a 22 SEER 9000 btu120V Mini Split hp. Magnum 4000 Inv, EPEVER (deployable array) and Midnite 250V main SCC. Nice cells from 18650batterystore south of Atlanta. See James.

 

[justinm001]

My SOK 48v 5kw rack batteries are amazing and work flawlessly. Communicate with CerboGX which makes the shunt basically pointless. Not only does it give SoC but the temp, voltage and any alerts are passed through. Couldn't be happier!! My only complaints are I put them with the screen pointing up and it seems everytime I put a tool or something on top of them i flip the dip switches. Also I cut a hole in metal next to it and all the shavings went on the screen which scratched them a bit. But completely my fault for not being cautious.

I have EG4 12V 5kw racks but the V1 without BMS and they work but not nearly as good as the SOK ones. I much rather having 2 posts on each battery and a built in breaker so I can easily disconnect 1 or more.

I don't see the point in building your own when the cost of these rack ones with a case and everything aren't much more and once you figure your labor in setup they're cheaper.

 

[RV10flyer]

My SOK 48v 5kw rack batteries are amazing and work flawlessly. Communicate with CerboGX which makes the shunt basically pointless. Not only does it give SoC but the temp, voltage and any alerts are passed through. Couldn't be happier!! My only complaints are I put them with the screen pointing up and it seems everytime I put a tool or something on top of them i flip the dip switches. Also I cut a hole in metal next to it and all the shavings went on the screen which scratched them a bit. But completely my fault for not being cautious.

I have EG4 12V 5kw racks but the V1 without BMS and they work but not nearly as good as the SOK ones. I much rather having 2 posts on each battery and a built in breaker so I can easily disconnect 1 or more.

I don't see the point in building your own when the cost of these rack ones with a case and everything aren't much more and once you figure your labor in setup they're cheaper.

The one advantage to building them yourself. You know what’s in them, how to troubleshoot, no shipping a heavy battery for warranty that probably won’t be honored, I have spares of everything and if something goes wrong, I can have it running again the next day.

 

[justinm001]

The one advantage to building them yourself. You know what’s in them, how to troubleshoot, no shipping a heavy battery for warranty that probably won’t be honored, I have spares of everything and if something goes wrong, I can have it running again the next day.

I believe this is the difference between eg4 and sok. Sok has removable parts so parts can be field replaceable. My EG4 bmss died and they RMAd them no problem but needed to ship batteries back and forth nbd since they covered freight both ways.

If I was building a large bank (which im planning) ill likely use batrium bms and custom bank. Mainly because batrium is great and I can physically build it to fit a certain size area.

 

[Bob B]

It's hard to beat the benefits of the Calb cells for their temperature range and proven reliability in an RV

 

[RvNaut]

Today, if I were starting fresh, I'd consider three (or more) of the 24v, 5Kw rack mount battery packs from EG4 or equivalent.

I built a 48v 16 x 280 battery, using a jobsite toolbox, closed cell neoprene and a Overkill 16s BMS. All in was $3k. If the goal is a big battery, economics still favors a self built, but it is getting very close. My cells were $160 each in March of '22. I checked last month and they were down to $136. Here it is in Bench Build Mode.