Professionals from lithium ion battery manufacturers advise you that you need to provide the following information when buying lithium batteries. you need to provide the following information: Rated voltage(V) Operating voltage range(V) Capacity(Ah) Charging current (A)(Rated current/ Maximum continuous current/Peak current) Discharge current (A)(Rated current/Maximum continuous current/Peak current) whether it needs to be in series or parallel, and if so, how many in series or parallel. Our lithium ion battery factory engineers will recommend the most suitable and cost-effective lithium ion battery packs