My odyssey with LEOCH batteries.

It all started when the solar installer delivered 2 stolen battery packs. I have written about it in a separate post. This way I got in contact with Averge, the sole official distributor of LEOCH batteries in SA. After I returned the stolen packs I purchased 2 packs 48100TB directly from them and installed. I had some issues with them as the user manual did not provide correct information how to connect them to the computer for monitoring. Finally the packs hat to be interconnected and connected with RS485 to the computer. They finally delivered the correct adapter and software free of charge. I edited their user manual for them in that respect as well as for some nonsense computer translation from Chinese.
Some months later I purchased a 3rd pack. The batteries performed to my satisfaction.
One year later I purchase the 4th pack. To my surprise it came with a different front plate layout. Also in service it showed to have significantly lower internal resistance. The BMS reported 103Ah capacity as compared to 100Ah of the others. So far not a problem. However with time the BMS got havoc. I.e. at almost 51V it reports only 54% SoC whereas the others parallel connected are at well over 92%. I observed when the sun managed to fully charge the packs, at 52V this BMS suddenly jumped from about 50% to 100% SoC. But then at discharge it somehow got back down to 10% when the other packs were at around 50%. It looks like the BMS had a problem with correctly metering the in and outgoing Ah.
I tried to contact Averge technical service but did not get any answer on email nor at the phone. I entered a message on their website but no answer. After a few more months I got tired and emailed to LEOCH SA office, asking them what happened to Averge. They contacted Averge and required them to address my problems. Then things started to move. Technical service contacted me so I could explain them the issue, backed with screen-shots of BMS readouts. They finally asked me to send the pack in to their branch in Cape Town for inspection. So I did. After a week they concluded that the pack is faulty to be replaced under guarantee. They asked me to organize the shipping back of the replacement pack. At this moment I decided to purchase another pack so the two could be shipped together. The two arrived some days later and I installed them.
To my surprise they are of a new type with again another layout of the front plate. It features RS232, RS485 and a CAN port. But in order to read via the RS485 I had to change protocol in the BMS. The technical service helped with advises as the delivered user manual was for a previous version and did not cover that.
As a nice new feature there is a push button labelled "Pre-charge". It provides a circuit around the main breaker with a resistor in series. It serves to soft pre-charge the capacitors in the inverters after shut down of them. I tried it and it works.
The battery package includes 2 1m 35mm² cables fitted with lugs, each a RS232 and RS485 USB adapter and a RJ45 jumper cable to interconnect the packs.
However in service the BMS showed some bizarre behavior. First I noticed that they have significant lover internal resistance. That is not a problem. But the BMS reported strange values of SOC. Values way below the values of the older 3 pack connected in parallel. Either one was in contradiction with the battery voltage, assuming that they are of the same chemistry. Coming up to full bulk charge voltage they did not report 100% SOC but remained at around 90%. I decided to observe the matter for a while. With time they normalized somewhat and now display also 100% SOC like the others when full. However some minor discrepancy between SOC readings of the older and the new packs remains. It appears that the new packs have a BMS of different type or make. The batteries themselves seem to perform correctly.
Lately I shared my observation with Averge technicians. At least they sent me the new user manual in a pdf file. It looks quit comprehensive and addresses the interface with a variety of different inverters.
Overall it's a trilling experience. Before I had no knowledge about Lithium batteries nor BMS.

Hi there! What a journey hahaha. A litlle advice, batteries should be stuck together, when charge/discharge is high they could produce some heat, check the temp values reported by the BMS, also i see cable lenght are not the same. Maybe is 25mm2? Right? Your inverter shouldnt draw more than a 100Amps, otherwize it will produce a lot of heat, for more than 2 or 3 batteries i would go directly to busbars. Just some advice! Nice clean install btw

5 hours ago, Tsmithf said:

check the temp values reported by the BMS

I do! Temperatures run around 30°C ±5°. All within normal operating condition. The more packs you have the less individual current in the packs, the less heat production.

Considering wiring: The main cables are 35mm², the others 25mm². As I wrote in other threads the difference in internal resistance (Ri) between the packs is likely to be way higher than the difference of 25mm² cable length. As a matter of fact the last pack in row of the older ones actually draws the highest charge and discharge currents of them, despite having the longest wires. The new packs in front have significantly lower Ri therefor draw even higher currents.

I think I found the ideal wiring by connecting the main cables in the middle of the row. There the current is split in 3, one goes directly to the middle pack, the two others to the 2 packs each at end of row. Its like having a 50mm² bus bar.

Tank you anyway for your considerations.

Edited November 5, 20241 yr by Beat

2 hours ago, Beat said:

I do! Temperatures run around 30°C ±5°. All within normal operating condition. The more packs you have the less individual current in the packs, the less heat production.

Considering wiring: The main cables are 35mm², the others 25mm². As I wrote in other threads the difference in internal resistance (Ri) between the packs is likely to be way higher than the difference of 25mm² cable length. As a matter of fact the last pack in row of the older ones actually draws the highest charge and discharge currents of them, despite having the longest wires. The new packs in front have significantly lower Ri therefor draw even higher currents.

I think I found the ideal wiring by connecting the main cables in the middle of the row. There the current is split in 3, one goes directly to the middle pack, the two others to the 2 packs each at end of row. Its like having a 50mm² bus bar.

Tank you anyway for your considerations.

That good!! Btw i have 6 packs connected to busbar and SOC also is not always the same, sometimes one have more than the other ones and sometimes less

A friend of mine also had stolen Leoch. When I mentioned the risk to him he contacted the installer. No ways was his answer. When he wanted to add more of the same comms would not work. Contacted 1st installer and mentioned the theft issue again. Immediately the 1st installer removed the old batteries and supplies 2 new ones free of charge. Why? so quick the 2nd time round? 

1 hour ago, Scorp007 said:

Why? so quick the 2nd time round? 

The installer that delivered the stolen packs to me is no longer in business. I was contacted by MTN and informed that a criminal inquiry was under way. They identified their batteries on the base of my photos I had taken before turning them back.