zlymex Posted January 14, 2016 Share Posted January 14, 2016 6 minutes ago, I now HATE Walking!! said: Cool. The next time I have my Airwheel opened up, I may install an AMP connector. Where do you buy individual cells? Can you buy LiPo cell holders, like you can for AA and D cells? I bought many 18650 cells in a Chinese e-commerce site called taobao.com, I never use cell holders for large current situations such as EUC. Instead, I use solder. There are a lot of cell holder in a T260 but they are special and impossible to find. When I test a 18650 cell, I use a four wire heavy duty cell holder. Link to comment Share on other sites More sharing options...
I now HATE Walking!! Posted January 14, 2016 Author Share Posted January 14, 2016 Why does a cell holder have 4 wires? Is there one wire pair for each of two batteries in the holder? Thanks. Link to comment Share on other sites More sharing options...
zlymex Posted January 14, 2016 Share Posted January 14, 2016 33 minutes ago, I now HATE Walking!! said: Why does a cell holder have 4 wires? Is there one wire pair for each of two batteries in the holder? Thanks. Two thick wires for current, two thin wires for voltage reading that direct from the cell terminal to eliminate the contact resistance/voltage drop due to large current. Link to comment Share on other sites More sharing options...
I now HATE Walking!! Posted January 15, 2016 Author Share Posted January 15, 2016 Thanks for the info. Link to comment Share on other sites More sharing options...
Mono Posted January 16, 2016 Share Posted January 16, 2016 @Jurgen, right, my considerations were solely targeting maximal battery life time. If we want on the other hand to maximize the range or the driving experience for the next ride, we need to charge to 100%. Life ain't always easy. Link to comment Share on other sites More sharing options...
Cloud Posted January 16, 2016 Share Posted January 16, 2016 55 minutes ago, Niko said: @Jurgen, right, my considerations were solely targeting maximal battery life time. If we want on the other hand to maximize the range or the driving experience for the next ride, we need to charge to 100%. Life ain't always easy. Did anyone ever answer this question?: what to do to get maximum mileage out of the battery over its life time? What good is extending battery life for another year if we have to make mileage sacrifices every day by charging to 70% and stop riding at 30%? For a heavier guy like myself, for example, my 840 wh battery only allows me 22-24 miles per charge, so for me to only use 40% of the battery every ride means making sacrifices by either not getting where i need to go or reducing the fun time when i ride for fun. I would think that ultimately one would want to get the maximum mileage out of the battery , not just for one trip, but over its life time, rather than get the longest battery life. will the recommendations in this case stay the same or should they change? perhaps they should change to this?: 1. if you know that 40% of the battery can cover your immediate trip today, and before the next trip, say, also today that can also be covered by 40% of your battery and you have an opportunity to recharge between the trips, then start charging at 30 and stop at 70% battery. If your second trip cannot be covered by 40% battery or if you dont have time to recharge from 30 to70% between trips, charge to 100% before the first trip to make up the shirtage of charge or the shortage of time. 2. if 40% of the battery cannot cover your trip , or say when you ride for fun and want to ride as much as possible, start charging at whatever percentage you are from the last trip and charge to whatever percentage will cover your riding today, a100% is ok if not sure. 3. Avoid deep discharge if possible. Try to stop riding closer to 30% if practical shoukd these be the rules that will maximize the mileage during batte life time, and also the practicality and the fun? what do the exprets say? Link to comment Share on other sites More sharing options...
Jurgen Posted January 16, 2016 Share Posted January 16, 2016 46 minutes ago, Cloud said: 46 minutes ago, Cloud said: Did anyone ever answer this question?: what to do to get maximum mileage out of the battery over its life time? What good is extending battery life for another year if we have to make mileage sacrifices every day by charging to 70% and stop riding at 30%? For a heavier guy like myself, for example, my 840 wh battery only allows me 22-24 miles per charge, so for me to only use 40% of the battery every ride means making sacrifices by either not getting where i need to go or reducing the fun time when i ride for fun. I would think that ultimately one would want to get the maximum mileage out of the battery , not just for one trip, but over its life time, rather than get the longest battery life. will the recommendations in this case stay the same or should they change? perhaps they should change to this?: 1. if you know that 40% of the battery can cover your immediate trip today, and before the next trip, say, also today that can also be covered by 40% of your battery and you have an opportunity to recharge between the trips, then start charging at 30 and stop at 70% battery. If your second trip cannot be covered by 40% battery or if you dont have time to recharge from 30 to70% between trips, charge to 100% before the first trip to make up the shirtage of charge or the shortage of time. 2. if 40% of the battery cannot cover your trip , or say when you ride for fun and want to ride as much as possible, start charging at whatever percentage you are from the last trip and charge to whatever percentage will cover your riding today, a100% is ok if not sure. 3. Avoid deep discharge if possible. Try to stop riding closer to 30% if practical shoukd these be the rules that will maximize the mileage during batte life time, and also the practicality and the fun? what do the exprets say? Did anyone ever answer this question?: what to do to get maximum mileage out of the battery over its life time? What good is extending battery life for another year if we have to make mileage sacrifices every day by charging to 70% and stop riding at 30%? For a heavier guy like myself, for example, my 840 wh battery only allows me 22-24 miles per charge, so for me to only use 40% of the battery every ride means making sacrifices by either not getting where i need to go or reducing the fun time when i ride for fun. I would think that ultimately one would want to get the maximum mileage out of the battery , not just for one trip, but over its life time, rather than get the longest battery life. will the recommendations in this case stay the same or should they change? perhaps they should change to this?: 1. if you know that 40% of the battery can cover your immediate trip today, and before the next trip, say, also today that can also be covered by 40% of your battery and you have an opportunity to recharge between the trips, then start charging at 30 and stop at 70% battery. If your second trip cannot be covered by 40% battery or if you dont have time to recharge from 30 to70% between trips, charge to 100% before the first trip to make up the shirtage of charge or the shortage of time. 2. if 40% of the battery cannot cover your trip , or say when you ride for fun and want to ride as much as possible, start charging at whatever percentage you are from the last trip and charge to whatever percentage will cover your riding today, a100% is ok if not sure. 3. Avoid deep discharge if possible. Try to stop riding closer to 30% if practical shoukd these be the rules that will maximize the mileage during batte life time, and also the practicality and the fun? what do the exprets say? I'm not an expert, far from. Main problem for me is that the relation between battery % and performance is not linear, so dificult to predict. A lot of headache for probably close to nothing in return. It's clear you don't start recharging when the battery is still at 95%. The only viable solution that I see, with the current wheels, is mainly for people using the EUC for their regular daily commute: in the evening you estimate the charging time based on the batt % that you have left when you arrive at home, and you plug a timer in between the socket and the charger (at your destination f.ex. work location you do exactly the same). Link to comment Share on other sites More sharing options...
Mono Posted January 18, 2016 Share Posted January 18, 2016 On 1/16/2016 at 7:38 PM, Cloud said: I would think that ultimately one would want to get the maximum mileage out of the battery , not just for one trip, but over its life time, rather than get the longest battery life. Maximum mileage is what I understand synonymously to longest battery life. EDIT: assuming comparable driving modes. As mileage per Watt hour can vary, talking about life Watt hours would be more precise. Link to comment Share on other sites More sharing options...
Cloud Posted January 18, 2016 Share Posted January 18, 2016 4 minutes ago, Niko said: Maximum mileage is what I understand synonymously to longest battery life. thats great to know. I thought what was meant was the battery effectively functioning over a longer time, say 3 years as opposed to 2 and a half, and i thought it may have been at the cost of compromising potential max. distance for each ride by charging to less than a hundred 100% Link to comment Share on other sites More sharing options...
Mono Posted January 18, 2016 Share Posted January 18, 2016 2 hours ago, Cloud said: thats great to know. I thought what was meant was the battery effectively functioning over a longer time, say 3 years as opposed to 2 and a half, and i thought it may have been at the cost of compromising potential max. distance for each ride by charging to less than a hundred 100% AFAICS you understood correctly. The differences are however much larger. You get at least 3 times the life time mileage from 30-70% charges compared to full cycles. That means, the battery lasts 6 years instead of 2 years, given the storage or other factors do not become decisive for its life time. Obviously, you can destroy the battery in all kind of (other) ways which makes any cycling strategy void. Link to comment Share on other sites More sharing options...
Cloud Posted January 18, 2016 Share Posted January 18, 2016 18 minutes ago, Niko said: AFAICS you understood correctly. The differences are however much larger. You get at least 3 times the life time mileage from 30-70% charges compared to full cycles. That means, the battery lasts 6 years instead of 2 years, given the storage or other factors do not become decisive for its life time. Obviously, you can destroy the battery in all kind of (other) ways which makes any cycling strategy void. I thought i understood before but now I am a bit confused again. You mentioned 3 times life time mileage increase ( with 30-70 cycle) and then you are saying 6 years vs 2 which technically will only give you about 1.3 times lifetime mileage increase if you charge once a day per both scenarios 1) 10 -100% cycle daily - you travel for 90% battery equivalent mileage daily for 2 years = 730 days by 90% battery equivalent miles = 65, 700 miles/ battery % 2) 30-70% cycle daily - you travel for 40% battery equivalent miles for 6 years = 2190 days by 40% battery miles = 87, 600 miles/ battery % 87,600/65,700 = 1.333 unltimately what i am interested in is, if i charge twice a day 30-70 % as opposed to once a day 10-100%, will i get more miles over the battery's lifetime and if yes how much more? Link to comment Share on other sites More sharing options...
Mono Posted January 19, 2016 Share Posted January 19, 2016 23 hours ago, Cloud said: if you charge once a day per both scenarios I never assumed you would charge once a day. Why would you? Why wouldn't you charge as often as needed to go as far as you want to go? A cycle does not mean a day. It means a charging cycle, and this usually means (de-)charging once from 100% to 0% to 100% or (de-)charging twice from, for example, 80% to 30% to 80%, or (de-)charging five times from 60% to 40% to 60%. Each of these would be one charging cycle, as each of these cycles delivers overall the same Watt hours. The strain on the battery of these three different charing cycles is very different. IIRC, you can do at least four times as many cycles of the third kind (and a single one means five times de-charging and charging) than of the first one. However I don't know how this number changes when you exchange the 0% with 10%. That is, I don't know whether close to zero or close to 100 percent is more of a problem here. 23 hours ago, Cloud said: unltimately what i am interested in is, if i charge twice a day 30-70 % as opposed to once a day 10-100%, will i get more miles over the battery's lifetime and if yes how much more? right, that was the question I was considering all the time. I am sorry that I was not clear. EDIT: to be precise, you would need to have 30-75% twice, if you compare to 10-100%. Link to comment Share on other sites More sharing options...
I now HATE Walking!! Posted January 19, 2016 Author Share Posted January 19, 2016 Maybe it is just me, but I like my tools and vehicles to just work and not strain my brain or require me to babysit them. I am just going to plug the thing in when I am not riding it. Don't get me wrong. I am an engineer and am all for optimization, but automation is important too. Hopefully, a battery genius will put code in the BMS to optimize all this stuff. Until then, I guess I will just buy a $90 battery every 2 years, so I don't have to think about this, daily. Link to comment Share on other sites More sharing options...
Cloud Posted January 20, 2016 Share Posted January 20, 2016 7 hours ago, Niko said: I never assumed you would charge once a day. Why would you? Why wouldn't you charge as often as needed to go as far as you want to go? A cycle does not mean a day. It means a charging cycle, and this usually means (de-)charging once from 100% to 0% to 100% or (de-)charging twice from, for example, 80% to 30% to 80%, or (de-)charging five times from 60% to 40% to 60%. Each of these would be one charging cycle, as each of these cycles delivers overall the same Watt hours. The strain on the battery of these three different charing cycles is very different. IIRC, you can do at least four times as many cycles of the third kind (and a single one means five times de-charging and charging) than of the first one. However I don't know how this number changes when you exchange the 0% with 10%. That is, I don't know whether close to zero or close to 100 percent is more of a problem here. right, that was the question I was considering all the time. I am sorry that I was not clear. EDIT: to be precise, you would need to have 30-75% twice, if you compare to 10-100%. Ok i understand now, thank you. I have a game plan then 1 hour ago, I now HATE Walking!! said: Maybe it is just me, but I like my tools and vehicles to just work and not strain my brain or require me to babysit them. I am just going to plug the thing in when I am not riding it. Don't get me wrong. I am an engineer and am all for optimization, but automation is important too. Hopefully, a battery genius will put code in the BMS to optimize all this stuff. Until then, I guess I will just buy a $90 battery every 2 years, so I don't have to think about this, daily. I am also like that, but consider this: 1. In 3 months (100 cycles) my battery effective capacity reduced by 30% so the way it was going there wasnt going to be 2 years. If it was looking like 2 years, i wouldnt even care to optimize 2. Where on earth will i be able to get a 680wh battery for 90$? Right now ninebot's 340wh extra battery is sold at close to $400. Besides, shipping batteries is not easy. Link to comment Share on other sites More sharing options...
Jason McNeil Posted January 20, 2016 Share Posted January 20, 2016 17 minutes ago, Cloud said: In 3 months (100 cycles) my battery effective capacity reduced by 30% so the way it was going there wasnt going to be 2 years. If it was looking like 2 years, i wouldnt even care to optimize @Cloud you said in another thread that your riding style was aggressive with lots of acceleration & braking. Even with 64 cells in the 680Wh/800W, a heavy guy doing this sort riding style will cause huge surges in the output, (& even worse) the input power to the battery pack during braking. The reality is there's a dearth of data on the detrimental effects of surge charging (from braking), or the impact of constantly topping up from 80%-100%, along with many other unusual usage characteristics of the EU & until someone conducts systematic testing with batteries to answer these questions, the simple fact is we just don't have a good enough understanding. Link to comment Share on other sites More sharing options...
Cloud Posted January 20, 2016 Share Posted January 20, 2016 7 minutes ago, Jason McNeil said: @Cloud you said in another thread that your riding style was aggressive with lots of acceleration & braking. Even with 64 cells in the 680Wh/800W, a heavy guy doing this sort riding style will cause huge surges in the output, (& even worse) the input power to the battery pack during braking. The reality is there's a dearth of data on the detrimental effects of surge charging (from braking), or the impact of constantly topping up from 80%-100%, along with many other unusual usage characteristics of the EU & until someone conducts systematic testing with batteries to answer these questions, the simple fact is we just don't have a good enough understanding. Yes, other things like frequent braking can have an effect too. But i guess there is no harm in trying to preserve the battery by charging to 80%. I will try to see how much difference does this make. Actually i have adopted a much more smooth riding style lately so the results wont be totally conclusive. Link to comment Share on other sites More sharing options...
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