I'm currently running 2x Svolt 48V 5.09kwh batteries with BMS, in parallel into my inverter. I need to add some more storage, but cannot find stock of the 5.09kwh i already have, but can get the 10.56kwh from the same supplier and manufacurer, same voltages.

I saw there were a bunch of threads about adding Pylontecs of various sizes together with no issue, is anyone aware if the same can be done for SVolt?

Edited November 17, 2025Nov 17 by Kibim

35 minutes ago, Kibim said:

I'm currently running 2x Svolt 48V 5.09kwh batteries with BMS, in parallel into my inverter. I need to add some more storage, but cannot find stock of the 5.09kwh i already have, but can get the 10.56kwh from the same supplier and manufacurer, same voltages.

I saw there were a bunch of threads about adding Pylontecs of various sizes together with no issue, is anyone aware if the same can be done for SVolt?

You will have to get the answer from Svolt or their suppliers. It all has to do with the comms. If on the other hand you work with voltage settings instead of the much more accurate measurements via comms you can still run different marks of batteries in parallel. A few of us are using voltage control with success. I have 2 DIY banks and I branded battery running in parallel. Each DIY with own BMS and branded battery without comms on my Deye.

Another option would be to try and buy another 5.09 kWh in the classifieds.

Edited November 17, 2025Nov 17 by Scorp007

See this offer https://powerforum.co.za/topic/32557-2x-svolt-48v-106ah-509-kwh-for-sale/#comment-220208

Same batteries if I am not mistaken

Not sure what exact battery the seller was referring to, but @Kibim might just run into the same problem with the bigger unit.

"Reason: Brought higher capacity 16cell unit and they cannot be connected in parallel with these 15cell units."

Best is to determine that both batteries have exactly the same characteristics, e.g. 15 vs 16 cells, cells = LFP, and BMS = the same.

Manufactures sometimes change the BMS to a newer/different spec when bringing out new lines.

If the batteries pass the first 2 tests, then you can try run them with "Comms" cable, else do as @Scorp007 suggest, just run them on voltage mode.

If the seller's batteries are still available, you should have very little problems.

6 hours ago, Sidewinder said:

Not sure what exact battery the seller was referring to, but @Kibim might just run into the same problem with the bigger unit.

"Reason: Brought higher capacity 16cell unit and they cannot be connected in parallel with these 15cell units."

Best is to determine that both batteries have exactly the same characteristics, e.g. 15 vs 16 cells, cells = LFP, and BMS = the same.

Manufactures sometimes change the BMS to a newer/different spec when bringing out new lines.

If the batteries pass the first 2 tests, then you can try run them with "Comms" cable, else do as @Scorp007 suggest, just run them on voltage mode.

If the seller's batteries are still available, you should have very little problems.

Yes the proposed battery is also 15 cell. SVolt give a 51.2V description if it is a 16 cell and also the capacity is indicated higher than 5.09 kWh adding the 16th cell.