Cerbera Posted December 12, 2016 Share Posted December 12, 2016 I've seen a lot of posts on the forum where everyone discusses batteries and how to look after them. So when I saw that Sci-show had done a video on Li-ion batteries, I thought of you guys first... I usually find their videos to be impeccably researched, so I trust we can rely on this advice. CBR Link to comment Share on other sites More sharing options...
abinder3 Posted December 13, 2016 Share Posted December 13, 2016 Don't agree with the "leave them plugged in all of the time". Allen Link to comment Share on other sites More sharing options...
Cerbera Posted December 13, 2016 Author Share Posted December 13, 2016 10 minutes ago, abinder3 said: Don't agree with the "leave them plugged in all of the time". Makes more sense with a phone than it does with an EUC.... I think the main point we can take from this is that we can prolong battery life if we limit the amount of electrons that pass through the electrolyte - ie if we charge to full when we are down to 70% everytime. I think that's sound, but it wouldn't be this forum if someone didn't think differently Link to comment Share on other sites More sharing options...
FreeRide Posted December 13, 2016 Share Posted December 13, 2016 The only way you are going to limit the electrons is to use it less. Once you've used 5Wh you used 5Wh does not matter if you charged it 5 or 10 times you have used the same amount of power. The Charger is an important part of battery life. Someone would have to test each EUC charger and pack together as a whole to see where each one could be improved, assuming they all follow the basic CI/CV protocol with 4.2V cut off. I think some though cut early and the different devices like CD that can be set to cut early. EUC probably never discharged down to 2.5V min, or even fairly standard 2.8V, I'm guessing they are curling off around 3 or 3.1V. No EUC uses the top high drain batteries yet that I've seen. Phone batteries are slightly different and you can be relatively sure each phone has a very optimum smart charge protocol. If you are going to store your wheel over the winter say, you certainly would not want to leave it plugged in. You would want to discharge it to roughly 3.5-3.7V per cell, providing it does not have a heavy parasitic drain. Knowing the parasitic drain of your EUC can be helpful to know what you should do. The manual for my minor says it does a trickle charge once full. I suspect that is BS, because they would know that that can kill these batteries faster. However if there is high ennough parasitic drain maybe they have some charge protocol and when to charger and it's not constant. With out real measurements it's a lot of guess work. It makes no sense to plug it in. It is true that it is likely better to recharge frequently, but not if your wheel is sitting a lot at full charge. the article does not really address issues with battery packs of multiple S/P cell configuration so it really isn't a good reference, but in this case again the charger circuit is very important and given the quality of some of the wheels in general I would not struct that the chargers are optimal. I don't think in general that video adds much useful information for EUC battery packs. Link to comment Share on other sites More sharing options...
Mono Posted December 13, 2016 Share Posted December 13, 2016 Agreed, the vid is not particularly helpful. Here is a short version in line of what @FreeRidesaid. Ideally (for the battery) - store at around 40% charge (while being aware of parasitic discharge) and rather below room temperature - charge directly before you go (from 40% store charge) - charge only as much as needed to get back home with 30-50% charge level left, in particular avoid charging over 90% and better recharge smaller amounts in between The bottom line to all of this: avoiding extreme charge levels in particular at high temperature. The effects of such a charging policy seem to be rather dramatic, i.e. it apparently can prolong battery life (in Wh) by a factor of 5 or so! Source: http://www.batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries Link to comment Share on other sites More sharing options...
Cerbera Posted December 13, 2016 Author Share Posted December 13, 2016 1 hour ago, Mono said: Agreed, the vid is not particularly helpful. Ok - my mistake - I will delete the thread. Oh, except I can't, so looks like we're stuck with it Link to comment Share on other sites More sharing options...
Mono Posted December 13, 2016 Share Posted December 13, 2016 57 minutes ago, Cerbera said: Ok - my mistake - I will delete the thread. While the vid is not particularly helpful, I wouldn't say the same thing for the thread. Link to comment Share on other sites More sharing options...
nomad Posted December 14, 2016 Share Posted December 14, 2016 Charging to 100% could be called an 'overcharge' already but we most often want it because it almost doubles the capacity and we juice it up as far possible while still keeping a practical lifespan.. Especially in the winter we need extra capacity because the lithium batteries can loose so much in lower temperatures. It's like overclocking a computer, maximize performance at the cost of lifespan and efficiency. Any charging level is always a tradeoff between capacity and lifespan, but it's not linear, the capacity gained gets smaller and smaller while the wearing down of the cells gets worse and worse. At some point it's not worth the tradeoff any longer. We can choose the balance but they keep it simple and choose it for you. You can limit it lower if you care enough, understand the benefit and can live with lower capacity. But they are forced to keep it high by default in order to be competitive. The way to solve it is by having a huge, heavy battery that has twice the capacity you need and never charge above 80%. But we want compact and lightweight with max capacity, I think the general consensus is that it's worth it to charge to 100% even if it wears down the batteries faster in the process. That way you can use the full capacity when it's new and when it's worn down to 80% capacity fully charged, then you still have that 80% left, and when it was newer you had even more. You get a smaller, lighter and cheaper battery, after a year you get rid of the whole device or get a new battery anyway, or something along those lines... However with bigger, heavier and more expensive batteries it's definitely worth it to have longer lifespan, we can use the Charge Doctor for that. Maybe once a month you can do a full charge for cell balancing. What you should be thinking about is how much time the batteries spend over 80%, the cells do not like being at those higher voltages at all. That's why electrical cars limit the charge lower, because the battery is not practical or economical to replace and the device needs a long lifespan. EUCs with big batteries fall into the same category if used as a vehicle not only a cheap toy! Keeping a laptop plugged in constantly will wear down the battery way faster because it's being kept in a constant 'overvoltage' condition. On a Thinkpad you can set the start/stop limits, for example activate charging at <35% and deactivate at >45% or whatever levels you want, so you can leave it plugged in all the time and it will very seldom charge plus keep it around 40%! Otherwise you can charge it to about 40%, remove the battery and put it away until you need it. But removing the battery is not an option for an EUC lol.. it's just a recommendation for a desktop replacement laptop... Controlling the max charge level in the bluetooth app would be a great and valuable feature. Of course this needs to be implemented in the hardware and firmware to begin with. We should request this from the manufacturers, at least for the more expensive wheels with massive battery packs. But until then we have the nifty Charge Doctor saving our batteries! Link to comment Share on other sites More sharing options...
US69 Posted December 14, 2016 Share Posted December 14, 2016 The best written articles about batteries and all questions are -my 2 Cents- still over there at batterieuniversity.com, this one for example: http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries Link to comment Share on other sites More sharing options...
Rehab1 Posted December 16, 2016 Share Posted December 16, 2016 I now have a better understanding on proper charging techniques. Thanks! Does anyone have information on riding in very CLD weather as I did today? I know EUC batteries should be kept warm before riding but are there any other issues, concerns or preparations? I am aware Li-ion batteries loose power faster in cold weather. @EUC Extreme has rode in extremely cold weather! Has anyone else? Link to comment Share on other sites More sharing options...
The Fat Unicyclist Posted December 16, 2016 Share Posted December 16, 2016 1 hour ago, Rehab1 said: @EUC Extreme has rode in extremely cold weather! Has anyone else? But I don't think @EUC Extreme uses Li-ion batteries... Link to comment Share on other sites More sharing options...
nomad Posted December 16, 2016 Share Posted December 16, 2016 If the wheel is used on a schedule such as commuting to work or school and you need to have 100% charge.. Then you can also use a wall outlet timer which costs like €10-15. So for example if your battery takes 3 hours to charge and you need to go at 7 o'clock in the morning with a fully charged battery, then you can set it so charging starts at 4 o'clock while you sleep. It's not recommended to charge while sleeping because of all the exploding and fire but what can you do sometimes? I guess a timer can even be used in combination with a Charge Doctor, if you want to limit the time the batteries spend at 80% too! The timer would start the charging and the CD would always stop it at 80% like usual even with varying discharge levels. Link to comment Share on other sites More sharing options...
Shoe73 Posted December 16, 2016 Share Posted December 16, 2016 4 minutes ago, nomad said: It's not recommended to charge while sleeping because of all the exploding and fire but what can you do sometimes? At least make sure there is a smoke alarm where you charge it. Link to comment Share on other sites More sharing options...
EUC Extreme Posted December 16, 2016 Share Posted December 16, 2016 Correct. I use almost all of my EUC lipo batteries. In my riding they do not need to be heated if the frost is not as -20. They remain very warm with exertion. If freezing temperatures are -25 ° C or more, I put the heating on. I do not like li-ion batteries, due to their poor performance. Fast voltage drop, and slow download In freezing temperatures the voltage drops very quickly at the slightest exertion. Link to comment Share on other sites More sharing options...
Flash Posted December 16, 2016 Share Posted December 16, 2016 13 hours ago, Rehab1 said: I now have a better understanding on proper charging techniques. Thanks! Does anyone have information on riding in very CLD weather as I did today? I know EUC batteries should be kept warm before riding but are there any other issues, concerns or preparations? I am aware Li-ion batteries loose power faster in cold weather. @EUC Extreme has rode in extremely cold weather! Has anyone else? it looks like they cant deliver so much current when its cold , I had to go slow back home , and the battery meter moves from 45% to red almost 0% when I push it , still I have 1360 wh , I dont know if more batteries would solve this Link to comment Share on other sites More sharing options...
FreeRide Posted December 16, 2016 Share Posted December 16, 2016 9 minutes ago, Flash said: it looks like they cant deliver so much current when its cold , I had to go slow back home , and the battery meter moves from 45% to red almost 0% when I push it , still I have 1360 wh , I dont know if more batteries would solve this No, for Li-Ion you generally don't want to be below freezing for the battery temp, but +10C is much better and 25C ideal. Your need some sort of heating solution to get better efficency below 10C. Of course the current models are not expected to be used in such temperatures. A sealed heated enclosure can be electrically heated but in some situations waste motor heat could also be captured and use to warm the batteries. There is not much space available on EUCs so an insulated enclosure with electric heat is probably the most practical. regenerative energy from breaking could be redirected to heating in low temperatures. I don't know how much better the Lipo batteries are at low temp, but EUC Extreme seem to have done his research. Lipo packs can also deliver much higher currents. Link to comment Share on other sites More sharing options...
Smoother Posted December 16, 2016 Share Posted December 16, 2016 33 minutes ago, Flash said: still I have 1360 wh , I dont know if more batteries would solve this 1360wh IS more batteries !!! 1020 MORE than I have to be exact. I'm having a little trouble feeling sorry for you. I'll try harder, I promise. ? Link to comment Share on other sites More sharing options...
Mono Posted December 16, 2016 Share Posted December 16, 2016 I would assume that if the wheel hasn't been stored outside, taking it outside for the ride should produce enough waste heat to keep the batteries above +10C. To my experience, battery temperature rises significantly above ambient temperature while riding. Link to comment Share on other sites More sharing options...
Flash Posted December 16, 2016 Share Posted December 16, 2016 1 hour ago, Smoother said: 1360wh IS more batteries !!! 1020 MORE than I have to be exact. I'm having a little trouble feeling sorry for you. I'll try harder, I promise. ? haha , I understand but still I want to solve the problem , maybe nuclear euc with free mutations included in the price Link to comment Share on other sites More sharing options...
esaj Posted December 16, 2016 Share Posted December 16, 2016 11 minutes ago, Flash said: haha , I understand but still I want to solve the problem , maybe nuclear euc with free mutations included in the price More batteries won't likely help much, instead you should look into temperature-controlled battery heating, that's what EUC Extreme uses, although I think those were custom-built for him. Posted October 19, 2015 · Report post Yes. I have now Gotway 18 with a battery heating. Battery is wound around a thin resistance wire. Then there is a meter which displays the battery temperature. I can self-adjust the temperature. In addition, there is an alarm to indicate too high or low temperature. It is really convenient for System Worldwide. Can run in -35 degrees below zero without any problems. Battery temperature remains easily 20 degrees. Link to comment Share on other sites More sharing options...
Rehab1 Posted December 16, 2016 Share Posted December 16, 2016 13 hours ago, EUC Extreme said: I use almost all of my EUC lipo batteries. LIPO? Ah man, I thought you would have installed the Flux Capacitor by now Link to comment Share on other sites More sharing options...
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