Can a capacitor prevent over-amperage of lithium ion batteries?
NO.

Batteries are simply capacitors with more toxic electrode/electrolyte combination which results in perhaps > 1k ~ 10k x more capacitance with a galvanic cell voltage but caps can withstand 10k times life charge cycles with lower ESR*C=T charge time {figure of merit} and less aggressive ageing on the materials.

But you can trickle charge the packs then dismantle them and locate the bad cells that are mismatched more than a few % in cell voltage by matching them in strings... If you search Youtube and find out how.  Pulse load tests are better and Ah tests are the best for matching.

Excessive current accelerates the imbalance in charge capacity and it only takes 1  bad apple to make a string fail.