Plyo Posted August 17, 2015 Share Posted August 17, 2015 I recently purchased a NB one E+ and really enjoys the Wheel. However it has a very scary fault to it. If I take it out fully charged and try to go downhill, the whole machine will suddenly power off unexpectently leading to some very nasty tumbles... You get no warnings and it doesnt break first, it just cuts the power in a second. When I pick it up and Power it on, it will run as normal, but if i keep on going downhill, it will happen again.If I however, drains the battery a little first by doing some random driving, it runs downhill silky smooth...What appears to happen, is that the regenerative breaking will start to recharge the battery when I go downhill, but if the battery is already fully charged, the problem occurs. If this is some kind of a short Circuit, or some kind of an overflow, I dont know??I live on top of big hill, so every time I take it out for a spin, I have to start by going downhill, so this is kind of a problem ;(Anyone else have experienced this, or even heard of this before With the Ninebot? Really appreciate any help. And for the record, the firmware is updated to the latest one Link to comment Share on other sites More sharing options...
RichieV Posted August 17, 2015 Share Posted August 17, 2015 I am guessing that the battery management system (BMS) is shutting things off to prevent the battery from overcharging. I'm just a layman, though, so I could be completely off base. Link to comment Share on other sites More sharing options...
Jag_Rip Posted August 17, 2015 Share Posted August 17, 2015 Hi Plyo, welcome to the forum I heard of this and as far as I read in here, there is nothing you can do about it (aside from major work that voids your guarantee prolly). You're best off draining a bit of power before you start to ride downhill. A few accelerations and harder brakings should do the trick, not sure if lifting the powered wheel off the ground on a regular basis is a good idea, but that drains power too.Unfortunately for you it only happens on this rare occasion where you immediately start running downhill after powering it up fully charged. Link to comment Share on other sites More sharing options...
Shader Posted August 17, 2015 Share Posted August 17, 2015 To me it sounds like something is wrong with your bot. Any overcharge normally would be handled by the internal logics on the 9b1 as far as my info goes.As an example, I usually start off with a fully charged battery going down a fairly long hill outside my house and I've never experienced that behaviour with my E+.I would contact the seller and ask for support. Link to comment Share on other sites More sharing options...
Jag_Rip Posted August 17, 2015 Share Posted August 17, 2015 I searched and found it, could be an issue similar to this one? Link to comment Share on other sites More sharing options...
Plyo Posted August 17, 2015 Author Share Posted August 17, 2015 Thanx a lot @Jag_Rip. This seems to be very similar to what I am experiencing. Looks to be a faulty battery, or charger, and not a bad firmware which I first expected. I eill contact the seller about this issue. Link to comment Share on other sites More sharing options...
esaj Posted August 17, 2015 Share Posted August 17, 2015 Yes, contact the seller and get it fixed. DO NOT modify the CHARGE-side protections of the BMS, from what I've understood, heavily overcharging a li-ion cell is asking for trouble, even an explosion. It's different (although not totally risk-free either) with the DISCHARGE-side protections, which are what is being bypassed in the BMS-shunt mod.From what I've understood, the wheel should burn off the excess power from regenerative braking as heat, if the battery cannot be further charged, but don't know if all/any wheels actually do this (although they must do SOMETHING with the energy from the regenerative braking even if they cannot cram it into the batteries, it cannot just vanish ).Avoid frequently over charging. Over charging with a low quality charger may let the battery's interior rise to a high temperature, which is bad for the lithium ion battery and charger. Thus, simply fully charging is good enough - overcharging will make your lithium battery into a little bomb if overcharge protection function is missing. Link to comment Share on other sites More sharing options...
patrickrho Posted August 18, 2015 Share Posted August 18, 2015 You know what I read this specific problem in one of the korean ninebot forums and the guy was furious that it was happening to him. The guy ended up changing his mainboard as well as his battery and the problem was resolved.Apparently, there have been multiple instances where ninebot shuts off going downhill. Well...faceplanting on concrete/asphalt while going downhill scares the crap out of me.. Link to comment Share on other sites More sharing options...
mengke Posted August 18, 2015 Share Posted August 18, 2015 If supplier cannot help you through, please consider the customer service channels listed in wheelyouride Google+ community. Link to comment Share on other sites More sharing options...
Dasferm.be Posted August 18, 2015 Share Posted August 18, 2015 When i bought my 9b1 here in Belgium, the dealer warned and explained this to me. He added also a 1 page usermanual in dutch that explains this and much more. It was better than the one in the box. For example:check your tire pressure; plug in 9b1 charge connector first an than wall plug. So thank you monowiel.be Link to comment Share on other sites More sharing options...
patrickrho Posted August 18, 2015 Share Posted August 18, 2015 When i bought my 9b1 here in Belgium, the dealer warned and explained this to me. He added also a 1 page usermanual in dutch that explains this and much more. It was better than the one in the box. For example:check your tire pressure; plug in 9b1 charge connector first an than wall plug. So thank you monowiel.be What did the dealer warn you specifically? Link to comment Share on other sites More sharing options...
Dasferm.be Posted August 18, 2015 Share Posted August 18, 2015 Warned to not start downhill. There is a potection for overload on the adapter charger, but not on the battery itself. So if you live on a hill, just do not charge fully. Going downhill will charge the battery. I tested it with the batterylevel at 80% and took a 300 meter downhill, there the battery level was 87%. I concluded that charging downhil goes faster then charging with the adapter. Link to comment Share on other sites More sharing options...
patrickrho Posted August 18, 2015 Share Posted August 18, 2015 Warned to not start downhill. There is a potection for overload on the adapter charger, but not on the battery itself. So if you live on a hill, just do not charge fully. Going downhill will charge the battery. I tested it with the batterylevel at 80% and took a 300 meter downhill, there the battery level was 87%. I concluded that charging downhil goes faster then charging with the adapter. Whoathat's crazy how much it charges the battery just by going downhill. Never knew that. Thanks for the info Link to comment Share on other sites More sharing options...
Jag_Rip Posted August 18, 2015 Share Posted August 18, 2015 Theres this video of that guy going Kitesurfing with his ninebot. So it seems this would really charge the battery quick Link to comment Share on other sites More sharing options...
RichieV Posted August 18, 2015 Share Posted August 18, 2015 Can safe testing can be conducted on a treadmill? Maybe it's not just Ninebots experiencing this problem. Link to comment Share on other sites More sharing options...
mengke Posted August 18, 2015 Share Posted August 18, 2015 It is universal issue.... Even Tesla cars have similar issues regarding recharging downhills with full battery. Link to comment Share on other sites More sharing options...
Mono Posted August 18, 2015 Share Posted August 18, 2015 Yes, contact the seller and get it fixed. DO NOT modify the CHARGE-side protections of the BMS, from what I've understood, heavily overcharging a li-ion cell is asking for trouble, even an explosion. It's different (although not totally risk-free either) with the DISCHARGE-side protections, which are what is being bypassed in the BMS-shunt mod.From what I've understood, the wheel should burn off the excess power from regenerative braking as heat, if the battery cannot be further charged,but don't know if all/any wheels actually do this (although they must do SOMETHING with the energy from the regenerative braking even if they cannot cram it into the batteries, it cannot just vanish ).There are physical limits to breaking (as they are to accelerating). You would need a comparatively large (e.g. >300W-or-so) heat sink for breaking a steep downhill path with full batteries. If you go down-hill and the wheel cannot turn over the incoming energy, what should it do? If it doesn't shut off, it will accelerate. Make your pick. EDIT: forgot the possibility of "active" breaking, in which case the heat sink would be the motor itself. Link to comment Share on other sites More sharing options...
mengke Posted August 18, 2015 Share Posted August 18, 2015 Heat sink would be the last thing to have with EUC... Link to comment Share on other sites More sharing options...
mengke Posted August 18, 2015 Share Posted August 18, 2015 Here is another electrical device with the same issue explained:http://boostedboards.com/faq/ Link to comment Share on other sites More sharing options...
Tishawn Fahie Posted August 18, 2015 Share Posted August 18, 2015 Hello - There - I honestly think there's something wrong with your Ninebot. I go down plenty of hills on a full battery and have never experience this problem. Mine have shut off on me countless times for random reason but i've never tumbled down a hill on a full charged battery. Something doesn't seem right. Link to comment Share on other sites More sharing options...
Plyo Posted August 20, 2015 Author Share Posted August 20, 2015 I just got an email from the seller. He tells me he has been in contact with ninebot, who is aware of this. The problem occured with the last firmware update, and they are working to resolve the issue. In the meantime I just gotta ride some more uphill Link to comment Share on other sites More sharing options...
Rotator Posted August 21, 2015 Share Posted August 21, 2015 What?I have the last firmware as well. I always start driving downhill. Never had a power cut.But now...I'm afraid of that! Link to comment Share on other sites More sharing options...
Mono Posted August 23, 2015 Share Posted August 23, 2015 Heat sink would be the last thing to have with EUC......is like saying the last thing to have on an EUC is a brake. Brakes convert kinetic energy into heat. Converting kinetic energy into heat is the only option left to actively slow down when the batteries are full (correct me if I am wrong). Link to comment Share on other sites More sharing options...
Jason McNeil Posted August 23, 2015 Share Posted August 23, 2015 @Niko is right, this is the approach IPS have taken rather than regen. In the perfect world manufacturers would adopt a hybrid system, that would dump only excess energy (more than the batteries can sustain) into heat, or when the battery pack voltage is already at max, 67.2v. Link to comment Share on other sites More sharing options...
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