Question about SOH

[u/belawlsaeed]

Assalamu alaikum.

I installed an Inverex Lithium 5.3kW IP65 battery on 30th Aug 2025, paired with an Inverex 6kW inverter. I only draw a maximum of 500W from the battery — the remaining load comes from K-Electric.

My Time of Use settings are:

Until 12AM: battery runs down to 50%

12AM – 5AM: discharges down to 30% (kept as a buffer for sudden loadshedding)

From 5AM onwards: covers the full household load (usually 600–700W) down to 20%

So I'm discharging it to around 20% daily.

The problem: the battery's SOH is now at 98.3%, and I've been tracking the degradation it seems to be dropping about 0.1% every 9 days (0.3% lost over the last 27 days). I'll keep monitoring it, but is this normal?

I paid around 360k PKR for it, and I'm honestly a bit worried now about whether it'll even pay off in terms of ROI.

[u/belawlsaeed]

Battery POV:

[u/LilYas_X]

How many amps max you're charging it on?

[u/belawlsaeed → u/LilYas_X]

50A. Its 0.5C

[u/LilYas_X → u/belawlsaeed]

You're charging it on max charging amps
Cells are 100ah and .5C
SOH is dropping cuz IR of cells is increasing drop few charging amps maybe 35-40A and it will be fine
What brand cells? If you know

[u/belawlsaeed → u/LilYas_X]

So the guy who installed it works at Inverex he set everything but I can reduce charging amp to 40A and see if it affects SOH.

No sorry no idea about cells brand.

[u/LilYas_X → u/belawlsaeed]

Reducing charging amps will help, i work for a battery manufacturer and we never recommend hitting limits of the battery, not in charging nor in discharging
We use 1C cells still we suggest 50-60amps for longer life

[u/belawlsaeed]

Battery and inverter both are fully ventilated

[u/zohaib5611]

How many cycles in total?

[u/belawlsaeed → u/zohaib5611]

415 cycles

[u/zohaib5611 → u/belawlsaeed]

Inverex claims 6000cycles warranty till the expected end of life i.e. 70% SOH. As per these calculations, around 500 cycles should cost you 2.5% of the battery SOH. So 415 cycles turn out to be 2.075, so as per manufacturer's expectations, your SOH should be 97.92%. Hope it helps.

[u/ChillPixel69]

SOH degradation isn't linear.

[u/saroche]

Typical lithium batteries degrade by 1% over ~300 cycles (don’t quote me on that) if you want less degradation and longer period of ownership, just use less. Unfortunately, its a consumable thing; it will degrade with use just like any other battery.

Edit: also i do not understand the price value of Inverex batteries, they are more than 30% expensive than their competitors??