ir_fuel Posted February 19, 2019 Share Posted February 19, 2019 2 minutes ago, US69 said: You are right...should!!! and whats left measured than is just the resistance of what the shutting mosfet lets through.... So has not to say much when such a voltage like 12V is measured. So the only way to know it is to have it drain itself to where it no longer turns on and then disassemble the battery pack? Quote Link to comment Share on other sites More sharing options...
US69 Posted February 19, 2019 Share Posted February 19, 2019 (edited) 16 minutes ago, ir_fuel said: So the only way to know it is to have it drain itself to where it no longer turns on and then disassemble the battery pack? to find out what? i suspect that it goes of about at 3,2 or latest 3 volts...so on a running and functioning wheel all no problem. just when you recieve it new...AND dead.....it is -for me- a serious question how far the battery was drained. Edited February 19, 2019 by US69 Quote Link to comment Share on other sites More sharing options...
ir_fuel Posted February 19, 2019 Share Posted February 19, 2019 11 minutes ago, US69 said: to find out what? this? --> On a separate note, has anyone ever posted what the actual battery voltages are for DOA wheels where they won't take charge? 11 minutes ago, US69 said: just when you recieve it new...AND dead.....it is -for me- a serious question how far the battery was drained. It will be the same as for others I think. They have the cells at storage voltage (3.8V) and they will slowly drain until they drop below 3.2V and get shut off. Makes you wonder how long some of those devices take between assembly and getting to the customer's door. Quote Link to comment Share on other sites More sharing options...
Planemo Posted February 20, 2019 Share Posted February 20, 2019 So from what I can gather from my original question, the BMS 'should' completely cut off the batts when cell voltage is down to 3.2v. Whilst this is 'good', the cells will still self-discharge after this point. How much depends on how long the wheel is stored. This leads me back to my original question of whether anyone has actually measured the battery voltage *prior* to using the 'kickstart' method. My concern is that the Z clearly has a high standby current which as we have suggested, is around 1% per day. After this, the BMS 'should' activate but if the wheel is then left in storage for another month or few, the cells could quite possibly be dropping below 2.5v which for me personally would be my absolute minimum voltage. Anything less and you are into risky territory - not something I would want to venture into with a £1500 wheel, given a replacement/re-celled pack will not be cheap. Quote Link to comment Share on other sites More sharing options...
Milan Vido Posted February 20, 2019 Share Posted February 20, 2019 16 hours ago, ir_fuel said: Makes you wonder how long some of those devices take between assembly and getting to the customer's door. Mine serial number indicate that it was manufactured on 47 week of 2018 so last November 19.- 25. Battery still had one bar left and started charging without issues. Also light looks to be never version (should be for all after week 44 of 2018). I ordered mine Z6 30.12. from Gearbest. It was marked as shipped and i received tracking number on 08.01. Then nothing until 24.01. when i received second tracking number for UPS Germany that they received label. Than again nothing until 11.02. when it arrived in Germany, from there it was quick and arrived in Slovakia on 13.02. but i was abroad until this Monday 18.02. when it was delivered. So in total it was 42 days according 1tracking.net, which would indicate that it was sent from warehouse only 08.01. Not sure if it was even at Gearbest warehouse at time of ordering or issuing of first tracking number:) I would say its quite quick turnaround from manufacturer to customer considering rail transfer from china. 1 Quote Link to comment Share on other sites More sharing options...
ir_fuel Posted February 20, 2019 Share Posted February 20, 2019 2 hours ago, Planemo said: Whilst this is 'good', the cells will still self-discharge after this point. How much depends on how long the wheel is stored. Unless something is actively drawing current, cell-discharge is nearly zero. Li-ion cells hardly lose any charge when left in storage in normal, room temperature, conditions. I have plenty of examples here at home that confirm this. The first one being my Rockwheel GT16 that has the same charge after 3 months of not using it. They might degrade (lifetime, internal resistance etc) when left on full charge for a long time, but they won't drop from 4.2 to 3.8 V by themselves over a period of a couple of months. That's one of the big differences with other battery tech that does (lead acid batteries for instance). 1 Quote Link to comment Share on other sites More sharing options...
Smoother Posted February 20, 2019 Share Posted February 20, 2019 Welcome @Milan Vido let us know about your Z10 experience, when you have some miles on it. Quote Link to comment Share on other sites More sharing options...
Milan Vido Posted February 20, 2019 Share Posted February 20, 2019 Thanks since its firs wheel for me i started only with z6 Quote Link to comment Share on other sites More sharing options...
Heyzeus Posted February 20, 2019 Share Posted February 20, 2019 I personally wouldn't trust any wheel that was delivered DOA regardless of manufacturer. For an inherently unstable platform with no safeties or redundancies I'm just not going to put myself at risk with something that doesn't work straight out of the box. Sure maybe you can jumpstart it and get it to work but you really shouldn't have to and if it's got issues up front then there's a strong likelihood that it might have issues later...when least expected. Lull you into a false sense of security and then bam. There's enough potential problems that could go wrong with one of these things why add something else into the mix. Every time the wheel would have some weird behavior or let's say you thought the wheel cut out but you really overleaned it, or pushed it past its performance capabilities, well you're going to wonder did it fail because of me or did it fail because it's got a bad cell. To me it just wouldn't be worth the risk and I would be sending it back...and that's besides the fact that for the price it should just be working out of the box. Not telling anyone what to do just you know rambling my thoughts Quote Link to comment Share on other sites More sharing options...
stephen Posted February 20, 2019 Share Posted February 20, 2019 So my z10 arrived and out of the box it started charging up when i borrowed a charger ,, mine didn't work 😐,, there was no bars on the dial and took a couple of hours for the first bar to show , so would you say mine hadn't died? Quote Link to comment Share on other sites More sharing options...
Heyzeus Posted February 20, 2019 Share Posted February 20, 2019 I'll let someone else who knows more about the z10 be the definitive answer but my understanding from what I read here is that if it takes a charge then the battery voltage hasn't dropped so low as to be disconnected by the bms and need "jumpstarting" if I am interpreting what I've read correctly it seems that if the battery voltage drops too low, the bms fully disconnects it from the system to prevent further drain and to protect the battery. It is in these cases where the battery may have dropped below 3.2v and where it will need a jumpstart but where there could potentially be damage to the battery. If your wheel turned on/beeped but wouldn't work due to low battery but still took a charge then you may be fine from a battery perspective. Others feel free to correct me if I am wrong Quote Link to comment Share on other sites More sharing options...
stephen Posted February 20, 2019 Share Posted February 20, 2019 26 minutes ago, Heyzeus said: If your wheel turned on/beeped but wouldn't work due to low battery but still took a charge then you may be fine from a battery perspective It didn't turn on as battery was to low but it did accept the charge when plugged in Quote Link to comment Share on other sites More sharing options...
Planemo Posted February 21, 2019 Share Posted February 21, 2019 15 hours ago, ir_fuel said: Unless something is actively drawing current, cell-discharge is nearly zero. Li-ion cells hardly lose any charge when left in storage in normal, room temperature, conditions. I have plenty of examples here at home that confirm this. The first one being my Rockwheel GT16 that has the same charge after 3 months of not using it. They might degrade (lifetime, internal resistance etc) when left on full charge for a long time, but they won't drop from 4.2 to 3.8 V by themselves over a period of a couple of months. That's one of the big differences with other battery tech that does (lead acid batteries for instance). Thanks for this. I appreciate that Li-Ion self discharge is very low, but it would still be nice to know exactly what we are dealing with when a re-cell of a Z10 pack could easily be £500. Like you, I suspect that the self-discharge would not be a problem in the case we are referring to, but it would be nice to *know*. A quick web search does not come up with any conclusive data, I have found quotes of '1% per year' for a 18650. On a 3v BMS cutoff, this would give 20 months before my personal minimum of 2.5v is reached. Whilst I accept that 20 months would be a long time for a Z10 to be sitting around after it's low voltage BMS had been activated, would it be unheard of? I don't know. Stephen - I think your wheel will be fine - if the pack charged from the stock charger (despite an initial delay) I do not believe your pack voltage would have been close to the permanent damage low voltage. It's the wheels that need the kickstart method which are likely to be nearer this point. 1 Quote Link to comment Share on other sites More sharing options...
stephen Posted February 21, 2019 Share Posted February 21, 2019 (edited) 1 hour ago, Planemo said: Stephen - I think your wheel will be fine - if the pack charged from the stock charger (despite an initial delay) I do not believe your pack voltage would have been close to the permanent damage low voltage. It's the wheels that need the kickstart method which are likely to be nearer this point. 😊 Thanks, and some good information you've been busy researching 😊 only time will tell i suppose , it's not just been one of two z10s what need kickstarting on the French furom there's alot of people done this too, haven't heard of any reports of completely dead to a point it won't charge, no one's had problems after they have kickstarted so we just have to wait and see , fingers crossed everyone's safe and stays safe Edited February 21, 2019 by stephen Quote Link to comment Share on other sites More sharing options...
Nic Posted February 21, 2019 Share Posted February 21, 2019 3 hours ago, stephen said: 😊 Thanks, and some good information you've been busy researching 😊 only time will tell i suppose , it's not just been one of two z10s what need kickstarting on the French furom there's alot of people done this too, haven't heard of any reports of completely dead to a point it won't charge, no one's had problems after they have kickstarted so we just have to wait and see , fingers crossed everyone's safe and stays safe If the batteries are damaged, then you will notice this with reduced battery capacity/shorter range ... granted you do not have a before/after to compare, so if range is good and close to what you expect from 1kwh battery (20+ miles aggressive riding, 30+ miles relaxed riding) then you are good. You will know what mileage should be expected for your riding conditions/style by comparing with your MSX with 1.6kwh battery and doing some simple math. 1 Quote Link to comment Share on other sites More sharing options...
Planemo Posted February 21, 2019 Share Posted February 21, 2019 3 hours ago, stephen said: 😊 it's not just been one of two z10s what need kickstarting on the French furom there's alot of people done this too, haven't heard of any reports of completely dead to a point it won't charge, no one's had problems after they have kickstarted so we just have to wait and see , fingers crossed everyone's safe and stays safe They will always kickstart, that isn't the problem. It's the long term damage that may have occurred due to cells going below minimum voltage (below the BMS level) that concerns me a little. This long term damage (by definition) will not be obvious until if/when people start getting premature failures on their Z packs. It won't be easy data to prove, given that in a year or two, trying to pin a failed pack down to a previous critically low voltage very early on in the wheels lifetime could be very difficult, if not impossible. The best data to go on is pack voltages for wheels that have required kickstarting, but we do not seem to have an abundance of this data. 1 2 Quote Link to comment Share on other sites More sharing options...
stephen Posted February 21, 2019 Share Posted February 21, 2019 18 minutes ago, Nic said: If the batteries are damaged, then you will notice this with reduced battery capacity/shorter range ... granted you do not have a before/after to compare, so if range is good and close to what you expect from 1kwh battery (20+ miles aggressive riding, 30+ miles relaxed riding) then you are good. You will know what mileage should be expected for your riding conditions/style by comparing with your MSX with 1.6kwh battery and doing some simple math. Quite surprised by the z10 milage 25 mile hilly traveling and 15-20mph and over average speed 😊 1 Quote Link to comment Share on other sites More sharing options...
Planemo Posted February 21, 2019 Share Posted February 21, 2019 14 minutes ago, Nic said: If the batteries are damaged, then you will notice this with reduced battery capacity/shorter range ... In my experience, this isn't always the case. I have had Li-Ions (in an E-bike fitment) which showed no initial reduction in capacity (post critical voltage situation), but their *lifespan* was certainly reduced compared to another pack which was never dropped below critical voltage. I don't want people to think I am trying to bash the Z at all, in fact I would love one, but I would just like to know what the packs are potentially dropping to, rather than relying on a 'they kickstart ok so it's no problem' situation. 1 Quote Link to comment Share on other sites More sharing options...
Nic Posted February 21, 2019 Share Posted February 21, 2019 53 minutes ago, stephen said: Quite surprised by the z10 milage 25 mile hilly traveling and 15-20mph and over average speed 😊 How much battery was left after the 25 miles? Was is down to low battery warning? Quote Link to comment Share on other sites More sharing options...
Popular Post Marty Backe Posted February 21, 2019 Popular Post Share Posted February 21, 2019 2 hours ago, Nic said: How much battery was left after the 25 miles? Was is down to low battery warning? Just wait til to experience the lovely Z10 low-battery warning. Unlike our other wheels, where you can still ride some miles at reduced speed, the Z10 will become almost unridable instantly. When the alarm kicks in, the pedals start tilting back and you have to reduce your speed to literally ~3-mph. So you can be cruising at 17-mph and them BAM, you're reduced to walking speed and maybe a mile or so of range. Useless as a warning. This happens around ~10-percent. 2 2 Quote Link to comment Share on other sites More sharing options...
Nic Posted February 21, 2019 Share Posted February 21, 2019 1 minute ago, Marty Backe said: Just wait til to experience the lovely Z10 low-battery warning. Unlike our other wheels, where you can still ride some miles at reduced speed, the Z10 will become almost unridable instantly. When the alarm kicks in, the pedals start tilting back and you have to reduce your speed to literally ~3-mph. So you can be cruising at 17-mph and them BAM, you're reduced to walking speed and maybe a mile or so of range. Useless as a warning. This happens around ~10-percent. is there any way to set a Warning in the App when a certain battery level is reached? This would be a useful feature. 1 Quote Link to comment Share on other sites More sharing options...
Marty Backe Posted February 21, 2019 Share Posted February 21, 2019 43 minutes ago, Nic said: is there any way to set a Warning in the App when a certain battery level is reached? This would be a useful feature. Not that I'm aware of. You just have to get to know your wheel and its range and never depend on the low-battery warning. 1 Quote Link to comment Share on other sites More sharing options...
stephen Posted February 21, 2019 Share Posted February 21, 2019 4 hours ago, Nic said: How much battery was left after the 25 miles? Was is down to low battery warning? About 22% 2 hours ago, Marty Backe said: When the alarm kicks in, the pedals start tilting back and you have to reduce your speed to literally ~3-mph. So you can be cruising at 17-mph and them BAM, you're reduced to walking speed and maybe a mile or so of range. Useless as a warning. This happens around ~10-percent I don't like riding to low of battery i try to judge my distance but i have got a 6amp charger in the post at 550 grams so might just carry that with me . It was 15 degees today did the same route very impressed with battery tbh here's today's screenshot 2 Quote Link to comment Share on other sites More sharing options...
stephen Posted February 21, 2019 Share Posted February 21, 2019 I might do the same route on my msx tomorrow try do the same speed and see what% i have left 2 Quote Link to comment Share on other sites More sharing options...
Nic Posted February 21, 2019 Share Posted February 21, 2019 4 hours ago, stephen said: I might do the same route on my msx tomorrow try do the same speed and see what% i have left Then you can compare both for efficiency in watt hours per mile... Watt hours per mile = Battery Watt Hours * (Battery Used Percent / 100) / Miles Watt hours per mile (Z10) = 960 * (63 / 100) / 21 = 28.8 wh/mile Watt hours per mile (MSX) = 1600 * (? / 100) / ? = ? wh/mile 1 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.