I suspect my LiitoKala battery contains used cells.
I purchased a total of four 12V 200Ah LiitoKala batteries in two separate orders via AliExpress from the LiitoKala Battery Store, apparently now operating under a different name, namely VariCore Overseas Warehouse Store. The batteries were very professionally packaged, and they looked good upon arrival — nothing to complain about in that regard. Unfortunately, one of the batteries started losing capacity significantly after a short period of time. Since I use them in a 24V 200Ah setup (two in series), the faulty battery made the whole system unusable. I contacted the seller, but we were unable to reach a solution. I also reached out to LiitoKala, the manufacturer, twice. Unfortunately, I never received any response. Out of curiosity and necessity, I carefully disassembled the faulty battery and was shocked to discover what appear to be used cells inside. In my opinion, this explains the battery’s poor performance. I plan to post a video about this on YouTube in due course, so that viewers can form their own opinions based on the facts.