batteries and chargers

[al.b]

Having had a 575 w wisper battery for almost 5/6 years, it began to deteriorate as I would of expected it to do so. Wisper kindly sold me a new battery again 575w but installing it on my 806 only showed 75% full. Plugged my original sans charger in but would only show all green and charged! Put support email in to wisper(not yet replied) But began to wonder about compatibility. In sheer frustration I bought another new charger again from wisper, plugged in and it charged the new battery. The output on the sans charger is 42v but the new one 36v but will not charge the original battery which still has little life left. Despite trawling the internet including the Chinese maker of the charger, no technical specs exist. I appreciate not all end users would require such technical specification but it would help diagnosing any faults which reading a lot of postings, seems to be current topic almost every week. All we know its a small black box which we plug into the battery and hope it safely charges and doesn't overcharge. the 575 w battery is big powerful battery but would expect there not to be a possible compatibility issue. I was tempted to buy a cheaper charger but the lesson maybe not all bike battery chargers are the same! Wisper only sell quality components but this episode, which was costly is timely reminder. I did find a very early posting in 2018 regarding issues with sans charger supplied with the bike. All you get is input voltage and output voltage on the casing itself, hope this may help other with same type chargers.

 

[wheeliepete]

Compatability issue with your chargers will prob. be down to the way the 3 pin charging plug is wired up which is often printed on the charger case. Both chargers are for a 36v battery, with 42v output voltage, so if wired correctly, will both charge either battery.

 

[al.b]

Thanks for that wheeliepete. The trouble is one charger outputs 42v and the other 36v, connections are the same, the 42v is rated at 2amp and the 36v 3amp. As all chargers will work on voltage sensing to start and end charging cycles, there may be some subtle differences although I agree they both should work but they don't! So in the end I will have to keep both chargers at the moment, restarted by the lack of a circuit diagram or more info,cheers

 

[vfr400]

Thanks for that wheeliepete. The trouble is one charger outputs 42v and the other 36v, connections are the same, the 42v is rated at 2amp and the 36v 3amp. As all chargers will work on voltage sensing to start and end charging cycles, there may be some subtle differences although I agree they both should work but they don't! So in the end I will have to keep both chargers at the moment, restarted by the lack of a circuit diagram or more info,cheers

|Did you measure the actual voltage from each charger? Does the 36v one say "output voltage 36v" or "charger for 36v lithium battery"? You can't charge a 36v battery of any type with a charger that only outputs 36v. You need 42v to charge a 36v lithium battery.

 

[al.b]

I totally agree, wisper thinks its a typo error on the case but when measured it outputs 36.5 v but yet charges the new battery but not my older battery and vis a versa. I can't measure the actual voltage under load either as the battery provides resistance. The manufacturer(chinese) is useless although to be fair it is CE marked. No matter onwards and upwards

 

[vfr400]

I totally agree, wisper thinks its a typo error on the case but when measured it outputs 36.5 v but yet charges the new battery but not my older battery and vis a versa. I can't measure the actual voltage under load either as the battery provides resistance. The manufacturer(chinese) is useless although to be fair it is CE marked. No matter onwards and upwards

You need 42.0v to charge a normal lithium battery. A LiFePO4 one requires a 43.8v one. Is there something special about the battery? Can you show a listing of it? Where did you get it from?