Hybrid battery refurbish

Hi All,

I got a question when I balancing my modules. Most modules are refurbished as expected, the discharge capacity increase as cycles go on. But there are several module behave weird. The discharge capacity was good at cycle 1 or 2, then in later cycle (3-5) charging stopped at very low capacity then following discharge capacity of course is lower too. my questions is why these several module behave differently than other good ones. why charging stopped at very low capacity?

My setting is below

Capacity cutoff 7250 mAH
Charge 2A
Discharge 1 A/6V
DCHG/CHG 5


see below the discharge/charge data

Discharge/Charge
Cycle 1: 2500 mAh/7250mAH
Cycle 2: 5500 mAh/680 mAh
Cycle 3: 564 mAh/360 mAh
Cycle 4: 300 mAh/590 mAh
Cycle 5: 550 mAh/720 mAh