It`s normal that after 2 years of charging/recharing , bateries lost it`s performance. But it`s no problem to exchange beteries. In this vacum model you need to buy any Li-Ion 18650 bateries (5 pieces for 18V model) . You need to remember only, to buy orginal bateries: (LG, Panasonic, Samsung etc). LG are dedicated for this modl but can be any other Lithium !! Capacity between 2500 - 3500 mAh Vacum has biulded BMS module only for this king of bateries. Exchange is very simple for each person who have basic knowledge about electronics or buildings RC battery package.
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