BMS can only handle 20 batteries!

yrtrnc
yrtrnc Solar Expert Posts: 54 ✭✭
Hi guys

I'm in a pickle.

I want to connect 32 100 Ah 12.8v victron lifepo4 smart batteries in a 51.2v 800ah config. Victron says its a no no as their bms can only handle 20 PCs. Something to do with the communication wires getting overloaded.

So my question is, is there a safe way around this? Maybe another brand bms? Or perhaps no bms at all?

System consists of 3 10000kva quattros in 3 phase. 20kw array with 5 victron 150/70 mppt chargers. Color control gx and a bmv 702 battery monitor. Victron BMS.

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    I will bump your post so that it can gather a few more views... But I really do not have anything useful to comment on.

    Perhaps you can talk to any large companies doing business in your region (Turkey?) directly besides Victron.

    You might find somebody that is engineering larger systems and would be interested in a "partner" to design and test at a live installation.

    Just out of curiosity, can you tell us a bit about your use? It seems to be a lot of power (30 kW of inverter, and a Li Ion battery bank with very high surge capacity) with a relatively small (kWH of battery bank) capacity system. Is this some sort of UPS (uninterruptible power supply) installation that just needs to keep power up for 15-30 munites until a backup genset takes over?

    -Bill

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • karrak
    karrak Solar Expert Posts: 326 ✭✭✭✭
    Maybe you should talk to someone else at Victron.

    "The BTVs of several batteries can be daisy chained. Up to ten batteries can be paralleled and up to four batteries can be series connected (BTVs are simply daisy-chained) so that a 48V battery bank of up to 3000Ah can be assembled. Please see our LiFePO4
    battery documentation for details."

    If they still insist that the BMS will only handle 20 batteries which contradicts their documentation you could ask them to swap the 100Ah batteries for 300Ah batteries.

    For safety reasons I wouldn't run a Lithium battery without a BMS.

    Simon

    Off-Grid with LFP (LiFePO4) battery, battery Installed April 2013
    32x90Ah Winston cells 2p16s (48V), MPP Solar PIP5048MS 5kW Inverter/80A MPPT controller/60A charger, 1900W of Solar Panels
    modified BMS based on TI bq769x0 cell monitors.
    Homemade overall system monitoring and power management  https://github.com/simat/BatteryMonitor