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miya avatar image
miya asked

Lithium and Lynx Smart BMS - Strange V behaviour

Hi All

New system -

  • 4x Smart Lithium 330Ah
  • Paralleled to Lynx Distributor
  • Connected to Lynx Smart BMS
  • With Lynx Distributor on loads side of BMS
  • Multiplus II connected to Distributor
  • Cerbo GX and Touch 70 powered off Smart BMS Aux
  • No other loads or charging sources attached
  • Brand new system - being commissioned

Batteries fully charged and balanced - multiple times. When the batteries are charging and discharging - I am seeing a strange behaviour in the voltage - which I wouldn't expect.

Discharging -

I would expect the V to drop quickly between 100% to 95% SOC and then remain fairly constant under a stable load until about 30% SOC - and then drop off quickly. I have only taken the batteries down to 50% SOC - but I am seeing the V drop, when under constant load to early -

  • with a constant load of about 5A the V sits at about 13.29v until 68% SOC
  • at 68% SOC the V starts to drop
  • it stops dropping at about 62% SOC and the settles at 13.13v
  • its then stays at this same V all the way to 50% SOC (I have not gone deeper yet)

Charging -

I see the opposite happening - the V rises quick between 62% and 68% SOC.

screenshot-2022-08-06-at-081802.png

My previous system (3x 200Ah Lithium and VE.Bus BMS) - never had this behaviour.

Am I worrying about nothing ?

Thanks all, Tim.

Lithium BatteryBMSlynx distributor
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1 Answer
Stefanie (Victron Energy Staff) avatar image
Stefanie (Victron Energy Staff) answered ·

@Miya

Yes I think so. We're talking of 150mV voltage drop or increase in a relatively short time frame. Nothing to worry about and quite normal. I see the same on my system.

Discharging - voltage drop of like 130mV at around 62%
bildschirmfoto-2022-08-06-um-105134.png


1 comment
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miya avatar image miya commented ·

Great - Many thanks Stefanie - and as always - thanks for your help.

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