I started my system 5 years ago with 2 Battery packs of LEOCH 48100-TB. I gradually added another pack, a second 5kW inverter in parallel and PV panels. So far it worked to satisfaction. Last year I added 3 more battery packs. LEOCH had in the mean time come out with a new model that is the 48100-S.

Now there is an issue with the new ones. While the 3 older ones with over 1500 cycles still show 100% SOH, the new ones after a few days of service showed 99% SOH. I complained about at the seller Averge. But Averge argues that if they can prove 100Ah capacity according to specs they do not consider this a guarantee issue. In the mean time a year later two of them have turned to 98% SOH.

Assuming the packs are still in good health and the algorithm in the BMS to calculate the SOH is correct, I conclude there must be a wrong parameter setting. But what is that parameter? Is there any BMS expert out there that could help?

10 hours ago, Beat said:

I started my system 5 years ago with 2 Battery packs of LEOCH 48100-TB. I gradually added another pack, a second 5kW inverter in parallel and PV panels. So far it worked to satisfaction. Last year I added 3 more battery packs. LEOCH had in the mean time come out with a new model that is the 48100-S.

Now there is an issue with the new ones. While the 3 older ones with over 1500 cycles still show 100% SOH, the new ones after a few days of service showed 99% SOH. I complained about at the seller Averge. But Averge argues that if they can prove 100Ah capacity according to specs they do not consider this a guarantee issue. In the mean time a year later two of them have turned to 98% SOH.

Assuming the packs are still in good health and the algorithm in the BMS to calculate the SOH is correct, I conclude there must be a wrong parameter setting. But what is that parameter? Is there any BMS expert out there that could help?

I wonder if the issue is with the new ones or with the old ones. 1500 cycles in and still 100%? The new ones I think are more accurate.

2 hours ago, Denns said:

I wonder if the issue is with the new ones or with the old ones. 1500 cycles in and still 100%? The new ones I think are more accurate.

Well, the specs claim a guarantee of 3500 cycles at 100% DOC. Since I never discharge that low I expect far more cycles before deterioration.

3 hours ago, Beat said:

Well, the specs claim a guarantee of 3500 cycles at 100% DOC. Since I never discharge that low I expect far more cycles before deterioration.

3500 cycles at 100% probably means you still have 80% of your battery capacity after that. That is the typical spec for Lithium batteries. So I wouldn't expect 100% SOH after 1500. Maybe some 95% if you aren't doing full discharges.

5 hours ago, Denns said:

3500 cycles at 100% probably means you still have 80% of your battery capacity after that. That is the typical spec for Lithium batteries. So I wouldn't expect 100% SOH after 1500. Maybe some 95% if you aren't doing full discharges.

That still does not explain the 99% SOH on brand new batteries after a few days in service nor the 98% SOH with some 400 cycles.

45 minutes ago, Beat said:

That still does not explain the 99% SOH on brand new batteries after a few days in service nor the 98% SOH with some 400 cycles.

Different storage temperature from where you bought them? They were used already? Can be a whole host of factors.

I understand why they may be reluctant to say there is an issue as what matter is that you SOH is over 80% after the 5 or 10 year warranty they gave you and the 3500 cycles.

Only issue is they may come up with a way to blame you if the battery doesn’t meet the stated warranty claim.

On 2025/10/21 at 9:06 AM, Denns said:

new model that is the 48100-S

Issue could be the different BMS.

The main differences are that the LEOCH 48100-S is an updated model with lower internal resistance and a newer BMS (Battery Management System), while the older 48100-TB has higher internal resistance. This means the new S model draws higher currents and may have issues with its BMS, which can cause inaccurate state-of-charge (SoC) readings that don't align with the terminal voltage.

LEOCH 48100-S

Newer model: Features updated technology and a different BMS.

Lower internal resistance: Results in higher charge and discharge currents compared to the TB model.

BMS inconsistencies: The newer BMS can show inaccurate SoC readings, sometimes much lower than reality, which can be a concern when running them in parallel with older models.

Potential for higher real capacity: The lower SoC readings could be due to the BMS being calibrated for a lower capacity, suggesting the battery's actual capacity might be higher than its stated 100Ah.

LEOCH 48100-TB

Older model: Was the previous version before the 48100-S was released.

Higher internal resistance: Draws less current than the newer S model.

Consistent BMS: The BMS in the older TB model provides more consistent and reliable SoC readings that align with the battery's terminal voltage

1 hour ago, Demo said:

The main differences are that the LEOCH 48100-S is an updated model with lower internal resistance and a newer BMS (Battery Management System), while the older 48100-TB has higher internal resistance. This means the new S model draws higher currents and may have issues with its BMS, which can cause inaccurate state-of-charge (SoC) readings that don't align with the terminal voltage.

This is exactly what I experience and described in my thread "Real capacity of battery". https://powerforum.co.za/topic/33176-the-real-capacity-of-batteries/

But the weird SOH reading is another issue.

On 2025/10/21 at 9:44 PM, Denns said:

Different storage temperature from where you bought them? They were used already? Can be a whole host of factors.

I don't think one can suspect Averge of selling used or incorrectly stored batteries for new. Their main customers are industrial such as cell phone operators. You don't foul them, you would be out of business in no time.

Edited October 26, 2025Oct 26 by Beat

On 2025/10/20 at 10:43 PM, Beat said:

I started my system 5 years ago with 2 Battery packs of LEOCH 48100-TB. I gradually added another pack, a second 5kW inverter in parallel and PV panels. So far it worked to satisfaction. Last year I added 3 more battery packs. LEOCH had in the mean time come out with a new model that is the 48100-S.

Now there is an issue with the new ones. While the 3 older ones with over 1500 cycles still show 100% SOH, the new ones after a few days of service showed 99% SOH. I complained about at the seller Averge. But Averge argues that if they can prove 100Ah capacity according to specs they do not consider this a guarantee issue. In the mean time a year later two of them have turned to 98% SOH.

Assuming the packs are still in good health and the algorithm in the BMS to calculate the SOH is correct, I conclude there must be a wrong parameter setting. But what is that parameter? Is there any BMS expert out there that could help?

Shot in the dark here!! Maybe: Firmware bug: If the battery is relatively new and shows a very low SOH, it could be a known bug in the firmware. You may need to update the BMS firmware to a newer version, as some earlier versions had this problem.

23 hours ago, TaliaB said:

Shot in the dark here!! Maybe: Firmware bug: If the battery is relatively new and shows a very low SOH, it could be a known bug in the firmware. You may need to update the BMS firmware to a newer version, as some earlier versions had this problem.

Bingo! This is the first significant answer to the issue - thank you. I'll call the seller to provide me the link for the firmware update.