Took delivery of my new Sprint7 on Monday. Very impressed! Documentation suggests (I think) that the battery should be fully charged, fully discharged, and then recharged. It says, "New battery needs to be conditioned with 2 or 3 full discharge and charge cycles before it comes to the full capacity". The impression I get from reading previous forum posts is that the Li+ battery profits from "top-up charging". These ideas seem to conflict. More probably, have I simply misunderstood? Which routine should I adopt?
Charging characteristics of Lith-ion batteries
- Thread starter redalpha3
- Start date
Definitely do three or four full discharges and charges first to condition the electrolyte, thereafter part charge as frequently as possible. Those first ones do no harm, it's continuously full discharging that slowly saps the capacity as it chemically ages the battery.
P.S. These conflicts of best practice are common with batteries. For example, batteries work best when at room temperature and rapidly lose efficiency when cold. Unfortunately, the Li-ions age most rapidly when warm, but very little when cold. Bound to cause confusion on which way to go!
P.S. These conflicts of best practice are common with batteries. For example, batteries work best when at room temperature and rapidly lose efficiency when cold. Unfortunately, the Li-ions age most rapidly when warm, but very little when cold. Bound to cause confusion on which way to go!
Last edited:
Thanks flecc
Helpful answer, as ever. Having to discharge the battery in small journeys as back is being bloody awkward at the moment. I wasn't aware that the Li+ had issues in a warm room!!! As you say, the characteristics of various batteries can be a little confusing.
Helpful answer, as ever. Having to discharge the battery in small journeys as back is being bloody awkward at the moment. I wasn't aware that the Li+ had issues in a warm room!!! As you say, the characteristics of various batteries can be a little confusing.
What I did with both the new Torq and Quando was to go on deliberate runs purely to eat up the charge in one go. This doesn't have to be to totally empty, below three quarters counts as a full discharge for running in battery purposes. That way I got this irksome part of ownership out of the way quickly.
Don't worry too much about the warmth, these figures for percentage loss in capacity for one year show how difficult this issue is:
- Storage Temperature - - - - -40% charge- - - - 100% charge
- - - - - - 0C - - - - - - - - - - - -2% - - - - - - - - - 6%
- - - - - -25C (room temp) - - - - 4%- - - - - - - - - 20%
Trouble is, charge needs to be at around room temperature, and usage near to that if possible. If the bike is used only intermittently, the ideal situation is to return with near 0% left in the battery and then put it in the fridge. Then, when it's going to be used again, it should be taken out again for return to room temperature, then charged to 40% and used before repeating that cycle.
The nearest equivalent to ideal for daily use is the shortest possible journey to zero and charge every time to enough for the next journey without worrying about temperature, with use of the fridge at weekends if the bike's not used then.
Faced with all those factors, it's probably best to just use and enjoy the thing and fork out for a battery when the time comes, you'll live longer that way without the worry!
Don't worry too much about the warmth, these figures for percentage loss in capacity for one year show how difficult this issue is:
- Storage Temperature - - - - -40% charge- - - - 100% charge
- - - - - - 0C - - - - - - - - - - - -2% - - - - - - - - - 6%
- - - - - -25C (room temp) - - - - 4%- - - - - - - - - 20%
Trouble is, charge needs to be at around room temperature, and usage near to that if possible. If the bike is used only intermittently, the ideal situation is to return with near 0% left in the battery and then put it in the fridge. Then, when it's going to be used again, it should be taken out again for return to room temperature, then charged to 40% and used before repeating that cycle.
The nearest equivalent to ideal for daily use is the shortest possible journey to zero and charge every time to enough for the next journey without worrying about temperature, with use of the fridge at weekends if the bike's not used then.
Faced with all those factors, it's probably best to just use and enjoy the thing and fork out for a battery when the time comes, you'll live longer that way without the worry!
Last edited:
Absolutely! Life is too short!
Only real problem is that once the battery is discharged in use I haven't the strength to pedal far unassisted. I might invest in another battery as a matter of course. In theory I would like a lighter battery that would do five miles or so for emergency use only!! I've seen somewhere (might be A to B) where a camera booster pack with lots of rechargeable AA batteries can be used. I have no experience of it though.
Definitely don't try an add-on battery like that with a Li-ion though Pete, potentially quite dangerous. A to B did make a mention of this, and they were doing it with NiMh on a Giant, a different matter entirely.
Just initially discharge to about 12 miles for those "running in" three or four runs, that way you wont be stranded as the bike can easily do that, then after that, for simplicity just charge to full every time you use it, or every few miles worth.
Just initially discharge to about 12 miles for those "running in" three or four runs, that way you wont be stranded as the bike can easily do that, then after that, for simplicity just charge to full every time you use it, or every few miles worth.
Absolutely clear. I'll do just that!
Theoretically though, surely if I simply connect another battery (Nimh for example) to the bike, isolating the Sprint battery, surely it wouldn't matter whether the Sprint had a Li+ battery or not? Is the motor any different? You can probably see why I wasn't a sparky in real life!
Theoretically though, surely if I simply connect another battery (Nimh for example) to the bike, isolating the Sprint battery, surely it wouldn't matter whether the Sprint had a Li+ battery or not? Is the motor any different? You can probably see why I wasn't a sparky in real life!
Yes, that's no problem Pete, I thought you meant the one wired into the other since that's what A to B did. So long as the battery is 36 volts it will run a bit, but if the capacity is below the normal 9A/h the performance might be a bit restricted, not a problem for a "get you home" though.
Charging a Li-ion battery
Peter
any time Night and Day!!!!!Never mind, that's what this site and my Torq Talk site are for, dynamic encyclopedias that answer back!
Peter
Related Articles
-
MTF Enterprises announces acquisition of EMU Electric Bikes- Started by: Pedelecs
-
Wisper 806T folding bike wins Which? ‘Best Buy’- Started by: Pedelecs
-
Sustrans calls for protected cycle lanes- Started by: Pedelecs
-
Amazon launch their first UK e-cargo micromobility hub- Started by: Pedelecs
