Adding batteries to 3 year old Dyness A48100

Hi all,

First post in several years. I have a question on behalf of my brother in law. He has a 8kW Deye system with a single Dyness A48100 battery, now about 3.5 years old. He wishes to add one or two additional bateries. The A48100 seems to have been discontinued. Would there be any issues to add one or two new 48V batteries (e.g. Dyness’ newer BX51100) be added in parallel, with BMS set to voltage mode?