Buying a second-hand e-bike can be a good way of starting your journey into the enjoyment and practicality of e-biking. But there are risks. The biggest question is always “How good is the battery?” For this reason, edevon-ebikes has been set up with a Battery Discharge machine, so that all the bikes displayed on this site will either have new batteries, or batteries that have been tested.
Testing the battery on a discharge machine will tell you what percentage of the original performance you can expect out of any particular battery.
During the uncertain period of the Pandemic in 2020 & 2021more ebikes were sold in the UK than either before or since. Sadly, many of those bikes were never really ridden and now they are appearing on the second-hand market with very few miles “on the clock”.
Lithium batteries do not like to be left idle for months on end and tend to degrade. The best performance from these batteries is on e-bikes that are used and re-charged every day. The exact state of the battery that has been unused for several months will depend on a number of factors
The Quality of the Cells
- The quality of the cells used in the manufacture. There are many cell manufacturers of various qualities. Some of the best are Samsung, LG and Panasonic. If you can find these names on a battery, that is a reassurance as to the quality of the battery. There are many Chinese cell manufacturers but, this may not be an indication of a poor battery. There are good and poor producers.
Battery Design
- The design of the battery. Some battery management systems (BMS) put the battery to sleep for prolonged storage. This preserves the cells. You can often tell that a battery has been put to sleep as when it is switched ON the bike it appears not to work. But, if the charger is plugged in for a few seconds, the battery springs into life!
How was it stored?
- The conditions of storage. Sellers will (nearly) always tell you that the battery has been well looked after and charged regularly. Visual inspection will not reveal whether the battery has been left in a frosty shed, left fully discharged for a prolonged period or, conversely cooked by being left plugged into the charger for weeks on end. These are 3 of the events that can damage a battery.
As a rough rule of thumb, lithium batteries loose 10% of their capacity annually. For example, a three years old 10Ah battery might now run to 7Ah. The rider will loose 30% of the expected range – say from 30miles on pedal assist to around 21 miles.
What to pay? An e-bike that has been stored for a couple of years should not deteriorate, other than the battery. With a new battery, it should be virtually “as good as” new. Add the price of a new battery to the cost of the bike and the sum should be well under the retail price of the bike. Do not forget that you are not paying VAT if you are purchasing privately. So, there is 20% saving.
A tested battery will give you some reassurance that you will get good use out of your second-hand e-bike for a year or two before inevitably purchasing a new battery.
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