Electric scooter battery
The accumulated experience in the repair of batteries for electric vehicles allowed us to write a series of articles on this topic. What would you like to reflect in them? Perhaps the problems faced by our clients in the operation of e-bikes and Segways, and gyrometers sigview.
Today we will talk about how to buy and operate a bundle of electric scooter battery in our conditions.
As a feature, it is worth noting that in most of Russia there is such a term as the seasonality of the use of electric scooters. This is often associated with a number of problems of battery failure. It is called – "ride in the fall" – "thrown discharged on the balcony or in the garage" – "in the spring got – zero battery." Here are some explanations are very often heard from our customers. As a result, if the battery is not too old, it is enough to "push" above the level of protection against over-discharge of the protection Board (bms) and it will still be able to please the owner, though with a smaller capacity. If the battery is 2-3 years old, then after such over-discharge it must be restored with extreme caution, it is not the fact that this can be done in principle and everything ends with a complete battery bulkhead.
The second feature is called "miser pays twice". The Segways there is a real "boom of sales", which recently happened with gyrometers. The market is in saturation, therefore, prices are going down. The battery is just the means of saving, which is actively used by various unscrupulous sellers. Let me remind you that the electric scooter battery, as a rule, consists of elements connected in series and in parallel. Parallel connection of several elements 18650 is responsible for the capacity and is one "Bank". Several cans connected in series give the necessary voltage at the ends of the chain. The electric scooter will not go if the voltage supplied from the battery is less than necessary to the controller, so you do not cheat with the number of cans. But a completely different picture with the capacity of the cans themselves. Leaving two 18650 cells inside the can instead of eight, the manufacturer will reduce the battery capacity and its cost four times. And it will not worry that the claimed mileage will not correspond to the actual, and to make a claim in this case will be almost impossible, since the warranty does not apply to the battery. As a result, after driving 3 meters in the store, and buying such a miracle of technology, you can get a mileage of 5 km, instead of the claimed 30. In such batteries, free space is engaged in all sorts of rubbish or just remain empty cells in the holders. To distinguish such a fake battery from the normal is almost impossible, they have a similar appearance and weight. But often our customers just believe the beautiful label on the shrink.
18650 what elements to put on the replacement? For several years of repair, we have not seen a single battery assembled on the original 18650. At best, they were acceptable fakes. Chinese manufacturers themselves are not interested in the production of good batteries, as the "original" will pull on 1/3 of the cost of electric scooter. We are always considering the repair of a pair of electric scooter battery, try to choose the best combination of elements 18650 to replace the failed. During the build "from scratch" approaches still more zealous, sorted cells internal resistance. Only this approach gives an acceptable result.
Another common problem is "defective bms". Like it or not, but if the manufacturer has not spared money and bought acceptable elements 18650, but cheaper with a protection Board, such a battery will die a long and painful death. This is especially true for large batteries, which do not see a big difference in voltage when unbalancing the cans inside. This generally leads to a General loss of battery capacity and uneven wear of the cans. In the end, the battery will stop charging correctly due to the drawdown of one of the cans and the road to the repair shop will be ordered.
"Overlookin of electric skateboard" – uncharacteristic for electric vehicle the term, but just wanted to drag it out of the 90-ies of the last century, when the processing power of computers was not enough and the users were trying to disperse it, increasing different multipliers and voltage. Here and now, some forget about the laws of common sense and do not regard the system of electric scooter battery as balanced. The people actively there is a thesis that if you increase the voltage on the battery. but the maximum speed of the electric scooter will increase. Of course, this is possible if the controller supports such a voltage and the motor-wheel can withstand an increase in the speed of rotation. But do you think that the Chinese manufacturer directly all Segways puts controllers with 30% headroom voltage and power? Usually, on the contrary, almost all of them do not reach 40% of the declared indicators and when driving at the maximum speed, this leads to overheating and their failure. Here at the time to reduce the voltage to reduce the load and extend battery life.
This is all for now, but read our other articles, we will continue to share the experience of repair. Interesting moments can always be left in the comments to the article.