How does your battery perform after a while ?

[SlowMo]

11 minutes ago, esaj said:

32 minutes ago, Cloud said:

Where can i get a charge doctor?

Hobby16 sells them, here's the topic:  http://forum.electricunicycle.org/topic/346-charge-doctor/

 

When you obtain the charge doctor, please keep in mind the connection sequence which is charger > power outlet > charge doctor > EUC otherwise you might blow up the resistor of the charge doctor which I have already done  and have the need to buy another one like me. 

[castShadow]

You probably shouldn't listen to me but - from my thinking I can't rely or don't rely on the charger telling me that the battery pack is fully charged.  Because it has been said that quick charging will charge to 80% easily and from there it gets much harder to charge and much longer to charge to 100% therefore I don't worry about the actual range or run-time that I get since it could easily have started at less than 100% charge.  I've also read many times that for longevity it is better not to deeply discharge a battery also not to fully charge a battery.  100% charging will put a lot of stress on the battery which is also why it is hard to charge to 100% - in my thinking I don't need the full range so a bit short of 100% doesn't bother me at all.  And discharging below a certain point will surely damage the battery or reduce its life.  If I decide, I'd leave 20%-25% of capacity left before I quit riding - quitting before that is fine too.  Also has been said that, don't recharge the battery until you are ready to ride it - that is to say if you are not riding it yet then it is going to be just sitting there and less than 100% charge is much less stressful to the battery - but of course don't store it too low either.  So they say the time to charge it is just before you go riding.

I've read that is the basic maintenance for battery longevity.  I've also had an electric car and I want another one and then after that, in the future maybe I can get a Tesla III (wouldn't that be nice?)  The history of electric cars in modern times is that some battery packs have been reported to last a crazy long time but they only use maybe 60% of the capacity - let's say charge only to 90% and use down to 30% - I'm making that up - in looking at it, for testing purposes I'd go even more conservative and charge to 80% and only use down to 40% (for long term testing of course) to maximize the life.  And this is another reason for getting a large battery pack - but the trade-off is it costs more and weighs more.  On an EU I would only worry about the battery if it is small to begin with because if you kill half of it, that would become really short range, like 3-mile range?  It could still be used for 1-mile trips though (1-mile to get there, 1-mile back, 1 to spare).  For a larger battery I would worry about taking care of it because I spent more money and so I'd want to try and stay within that window of charging and discharging (definitely a true full charge is stressful in all the documentation).  I don't really know the details on Tesla but doesn't the Model S only charge to 80% approximately and you have to specifically request in the menu to do the 100% charge?  Do they call it a long range charge or something vs a normal charge?  By default they do not do 100% charge.  Again the larger capacity will give you more usable range.

When I'm riding an EU with 4-lights indicating the charge, I only ride until there is one light left and then it's time to quit.  By anyone's guess that should be in the neighborhood of 25% charge left (or is it 20% if you count the gaps between lights and not the lights themselves).  Right now I'm riding a 540Wh wheel and it feels like it has massive range - with 8(?) lights I rode 15 miles and still had 5 lights left - and I didn't have time to charge it to the end until the green charger light so I don't know how full it was, but again I was fine with that - though normally I charge until the light turns green (at yet even then I don't know if it is 100% or less - some chargers I've read stop at less than 100 and you have to disconnect and reconnect and then it will continue charging to full?  I haven't tested this though.)  Anyway I was going particularly slow since I am still learning this wheel and probably being overcautious but definitely not riding it hard.  That probably accounts for the super-long range, the battery never overheating.  I only sped up a couple of times.  I think the tire is breaking in now and I probably don't have to worry about it slipping, but it felt slippery before plus other issues that's why I was being cautious.  Anyway, I'm not saying to ride like me - I was sight-seeing.  Actually I was test riding.  I think this size battery is plenty for my needs.  I don't plan to discharge it below 2 lights and also with this range I don't even need to charge it up to the full 8 lights -maybe I can use a timer to stop before a full charge -or maybe I won't worry about it at all and only charge before riding so that it will only be at max charge for a short time thus minimizing stress on the battery.

Edit: and I did forget to mention you're supposed to balance the battery charge between the cells by fully charging once in a while and leaving it plugged in after it appears fully charged.  My question though is how does the battery cells get unbalanced so that you may determine better how often it should be balanced. (For example maybe once every 5-10 recharges ? or half that many ?)

But remember I can be wrong in some parts of this, but maybe close enough in other parts though.

[Gimlet]

You've pretty much hit the nail on the head there castShadow. 

In the Tesla you can set the charge to whateverr percentage you want and it will charge to that amount every time until you change it back but the recommendation is 80% and only charge to 100% if you really need to and immediately before you set off so it doesn't stay at 100% any longer than necessary. 

[castShadow]

Cool @Gimlet  I see you have many large battery packs    How do you insert signature/notes like that at the end, or is that special privilege feature?

Ooh - never-mind, I just found the signature feature!