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Charger is broken :(


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Just a flashing red light from the charger and it's not charging the unicycle - I'm guessing it's borked.

I figure these chargers can't *just* be made for electric unicycles and I'd rather not wait for banggood to ship another from half-way round the planet.  Any ideas on where to find an equivalent charger that I could get more quickly - don't want to be without my wheel for weeks. :(



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Cheers - I've just ordered another and paid for faster shipping.  Do you know whether faster chargers have a bad effect on battery life?

This might help: http://batteryuniversity.com/learn/article/ultra_fast_chargers  Fast charging is said to have at least some effect on battery aging, but if you don't go overboard, it shouldn't have that much effect:


In general, with high quality cells, 1C charge rate shouldn't be a problem (http://batteryuniversity.com/learn/article/what_is_the_c_rate), although I think the manufactures rate some cell-chemistries at higher rates. Simplified, C-rate means the number of amperes used in charging (or discharging) in relation to the battery capacity. So a 2000mAh (2Ah) battery charging at 2A is charging at a rate of 1C, and should be fully charged in 1 hour (although in reality, the charger starts to drop the current towards the end of the charge, so probably takes a little longer).. 4A charging for similar battery would be 2C (should take about 30 minutes), 1A charging would be 0.5C (should take about 2 hours). If you have multiple packs, the charge / discharge current is divided among the packs. If you know their Ah- or Wh-capacity, you can calculate the amperage for 1 hour charge/discharge (1C) pretty easily:

Battery amp-hours per pack * number of packs / 1 hour, but you can leave the division by 1 hour off (divided by one). So for example, two 2.9Ah (2900mAh) packs that would be 2.9 * 2 = 4.8A

Or   (Battery watt-hours per pack / nominal voltage) * number of packs / 1 hour. For example for four 132Wh packs at 60V voltage, 1C rate would be (132 / 60) * 4 = 8.8A, for one pack it would be 132 / 60 = 2.2A. That's a pretty high current with the four packs, so another thing to take into account with fast (= high current) charging is that thinner wires can heat up considerably under high current for a longer time, as may the connectors, also the BMS(s) can limit the maximum current. You don't want to melt the wiring or burn the connectors with too much current ;)  When 1Rad Werkstatt was selling the >1kWh packs for MSuper, they were also selling a separate fast charger (8A), but said it shouldn't be used with normal MSupers, as the charging port (or maybe it was some other connector in the way between the port & packs) wouldn't withstand that high current.


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