How to charge e-bike batteries safely
Electric bikes and similar vehicles such as e-scooters or hoverboards are not only practical, but usually also expensive – not least thanks to the powerful and not entirely cheap lithium-ion batteries. E-bike owners naturally want their bikes to last as long as possible. In addition to normal maintenance – cleaning, lubrication and rust prevention – the service life of the batteries is particularly important. This is why many riders ask themselves how to charge e-bike batteries correctly. We provide the essential answers here.
First things first: If your lithium-ion battery is visibly damaged, deeply discharged or swollen, you should not charge it at all. The charging process could cause the battery to overheat and start to burn or even explode. In such a case, you can only dispose of the battery.
A further safety note: You should only charge your e-bike battery with the manufacturer's original charger or with a charging cable that is explicitly approved for your electric bike or its battery. The charging electronics and battery must be precisely matched to each other in order to function optimally. For example, different types of lithium-ion batteries sometimes work with different voltages. If the wrong power supply unit is used, the electric bike battery may not be charged at all or it may be overcharged. Just a few tenths of a volt can cause serious damage.
The good news when charging modern e-bike batteries: Unlike older models, lithium-ion batteries no longer have a ‘memory effect’. This means that you don't need to run the electric bike empty and then fully charge it. Instead, you can recharge it during a break, for example. In general, you should even avoid extreme charging states, i.e. do not let the battery become completely empty (risk of deep discharge) and do not always fully charge it. This applies in particular if you want to store your e-bike for longer periods, e.g. over the winter. Even if you need to fully charge the bike battery – e.g. before a long journey – you should not leave the battery on the charging cable unnecessarily after charging. Unplug it instead.
E-bike batteries should not be charged in extreme heat or cold, but at room temperature. Typical temperatures are around 10°C-20°C, exact details can be found in the operating instructions. You should therefore not charge your batteries outside or in an overheated garden shed in summer. Charging indoors is also the gentler option in winter. If you don't want to take your electric bike indoors every time, you should therefore choose an e-bike with a removable battery. You should also make sure that your e-bike battery has had enough time to reach room temperature before you start charging it.
A removable battery also has another advantage: Due to its small size compared to the bike, it is easier to charge it in a place where it will not cause a secondary fire if it catches fire while charging. If you want to be on the safe side, you can charge your electric bike battery in the fireproof RETRON BOX.
