Givenergy Battery Capacity Problems

Solarchaser

Ahhh.
I read round trip and assumed you meant from inverter in to inverter out.

Never assume...

2nd_time_buyer

Sorry to hijack the thread @ispookie666. Was after some help with my parents Givenergy system which is probably not a related issue. 

They have it set to charge the battery overnight which seems to be working okay. However, shortly afterwards there appears to be a drain of around 2.5kw for an hour or so on the battery. My parents say they have nothing running other than the fridge, nothing is being exported, and it doesn't seem to happen every night. I can't think where the power is going (nothing seems to be getting hot). Any thoughts?

ispookie666

Thought I'll put this out as a visual way of seeing the problem.  
Two batteries - Purple and Turquoise SOC,  their combined SOC - Deep blue  
Victron SOC - Orange



The batteries stopped discharging around 1:30 when the voltages hit 2.7 V per cell.  According to GE the combined SOC was 15% (individual batteries 18 and 21%) but Victron was sitting at 6%.  

Chart is extracted from Home Assistant, Victron smart shunt has had filtering to remove outlier values.  Inductive loads play havoc with ESP8266 extracted data, as they are polled every second! 

ispookie666

There was supposed to be a definite firmware release on the 16th to fix this issue and as expected in true GE fashion, its not coming.   I suppose the next Christmas will be here before the new firmware!

steveconrad

Afternoon.
I was wondering if what I've seen today is the same issue as reported above? My GE battery was installed mid Jan (9.8KWh) so today was one of the first times the sun has been out enough to actually charge from my solar.

Anyhow, around noon, the SOC for the battery suddenly shot up for no descernable reason. This is the output from the inverter data for that segment of time. 

Time	Status	VPV1	VPV2	VBAT	PBAT	TBAT	SOC%
12:53:09	NORMAL	120.8	122.2	54.4	0	18	100
12:48:08	NORMAL	121.3	121.1	54.61	0	18	100
12:43:06	NORMAL	120.9	120.8	54.88	0	18	100
12:38:04	NORMAL	120.8	120.8	55.6	0	18	100
12:33:02	NORMAL	122.8	121	56.77	-547	18	30
12:28:00	NORMAL	120.8	123.5	57.04	-723	18	30
12:22:58	NORMAL	120.9	120.9	56.3	-530	18	30
12:17:56	NORMAL	120.7	120.7	56.91	-1084	18	29
12:12:55	NORMAL	122.1	122.1	55.72	-348	18	29

This then seems to have caused the inverter (also GE) to start pumping out my solar juice to the grid when at least to me, there's probably enough capacity to store more. The battery was cycle tested to 100% when it was first installed, so I think it's behaving OK there. 

Is this something I have to live with for the moment? Or do I have a problem in the system somewhere?

Appreciate any thoughts.

ispookie666

@steveconrad Yeah that's typical behaviour /SOC bug

1961Nick

The battery voltage is all over the place & appears to have no relationship to the SOC. Something is very wrong.

ispookie666

@1961Nick This has been going for more than a year.  The promised deadlines from Givenergy has not materialised.  But there seems to be new firmware on the horizon which sort of addresses this but results in battery capacity tanking!

qwertyuioop

Following.

Hope GE come back with a solution soon.

joe956

Can I just add - I am in the same boat - we often see drops of 40% or more. I am also a HomeAssistant user and we now try to plan the battery so it discharges daily this way we know that once we get to 10-20% capacity it can drop to 0% at any time.
Yes they have been promising firmware fix but that is just that - unfulfilled promises .
For me personally getting GE battery and inverter was the worst purchase I have ever made.