if (as it looks) the cell holders easily part to give access to the individual cells, i can charge them in my "good" charger - https://www.amazon.co.uk/gp/product/B07KT1RPVR/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
in case this doesnt work, i might be struggling, but charging individual...