You should use and charge lithium-ion batteries correctly to get the expected lifespan from them. When you buy your vacuum cleaner, recharge the battery for at least 90 minutes. Batteries are shipped with a low charge for safety purposes, so you need to charge them before you first use the device.  After each use, put the battery for charging. Leave the battery to charge until the “fully charged” indicator lights up. Once fully charged remove the battery from the charger. Avoid over-charging batteries to avoid damage and for safety reasons. If the machine stops due to a low battery, remove the battery and put it for recharge.