FoxESS Community - Owners & Installers Forum

What sort of State of Health values are other HV25 users seeing on their batteries after having them a while?

I've had mine around 15 months now and have done 280 cycles in that time. However the SOH as reported in the Fox App says it is now only 96%? This seems quite low and is a bit worrying as they're supposed to be good for 4000 cycles before hitting 80% SOH.

I'm curious what others are seeing? The SOH reading can be found in the v2.0 app under Battery > Info > detailed parameters. The cycle count can be found in Me > Data with the reporting method as "standard" and in the excel csv file it is cycle count.

The SoH seems to only be available to the batteries which have the V2 BMS such as HV25, HV2600V2, ECS-V2, EP etc.. my V1's doesn't have it so unfortunately don't have any direct experience, but from what other users have said that is in-line with their observations for example one user with a 6 battery HV25 installed just over 14 months shows 96%.

I have been told LFP batteries have higher degradation during their early cycles which becomes flatter as they age - I haven't yet found a research paper which confirms that as they are typically investigating other affects when they compare (such as high or low temps).

Hopefully the initial degradation steadies off as you mention, otherwise I'll be hitting 80% SOH in about 5-6 years and 1400 cycles! I wonder where we'd be warranty-wise if that did happen?

The figure seems to be relatively accurate at least. As a year ago I could get about 10.5kWh from or into the batteries but that is more like 10.1kWh now.

I guess long-term data on these batteries is somewhat lacking still.

Thought it might be worth an update as at the ripe old age of 18 months since installation and only 390 cycles, it has just dropped to 94% SOH yesterday.

I'm starting to get a bit worried now. If the drop continues in a linear fashion Ill be at 80% SOH in 1300 cycles and under 5 years. I'm also struggling to get any more than about 9.7kWh into 12.28kWh of batteries.

Current total throughput on the 5 batteries is 8.24MWh. The Fox warranty document on the HV25 says they cover 8.9MWh throughput per battery down to a minimum of 60% SOH, so I'm about a fifth of the way there on both.

Anyone else with these batteries have figures for comparison? It feels like they're wearing quickly to me but for all I know it could be normal!

I’ve had my system which includes 3xHV25 with min SOC at 12%, for 20 months

My SOH is 92% with 630 cycles

4000 cycles is thus just over 10years but I do worry about the efficiency drop. I hope it levels out!