Retiring my Battery

[awol]

I am retiring my first original battery which has done me proud.
10aH Bottle battery, cost £230, aprox 13'000 miles, 3 years old, used for 20-miles daily.
We've had a good 3 years together used daily through all weathers and even submerged through knee high deep floods but is now at the point where it still charges up to 41.5v but I only get about 3 miles range from it before it passes out from exhaustion.
It is 10aH made of chinese cells by BMSBattery and total cost £230 which was a bargain with the service it's given me.
It was fully charged once a day for the first 18months or so, then twice a day for the next 18months or so as the range dropped.
Here it is when it was new.


And here it is now, about 13'000 miles later weathered and worn out.



I don't think I will have a downtube bottle battery again as I'd rather hide them in the bag at the back now
and I have the smallest of frames so getting them on/off may be a problem, lucky as I was this model slides off sideways.
I might remove the weakest and strongest cells and check them for capacity out of interest.
I will continue for now with my 20aH tonne weight breeze block I also bought 3 years ago hidden in the bag at the back but since it weighs nearly as much as me I'm not sure about the handling due to weight so will see tomorrow. Enjoy the retirement old friend.

 

[Deleted member 4366]

I might remove the weakest and strongest cells and check them for capacity out of interest.

That can be done, but it's not at all easy. I wouldn't bother. One of these should fit:

http://www.eclipsebikes.com/hailong-145ah-lithium-frame-battery-samsung-cells-p-1119.html

 

[KirstinS]

That can be done, but it's not at all easy. I wouldn't bother. One of these should fit:

http://www.eclipsebikes.com/hailong-145ah-lithium-frame-battery-samsung-cells-p-1119.html

Personally I would bother if you have the time.

I reuse them to power my front lights as long as they have at least 80% capacity left

 

[Deleted member 4366]

Maybe I misinterpreted that comment. I took it as meaning checkingthe capacity with the aim of repairing the battery.

If you scrap it, the good cells can go into those powerbank cases that only cost a couple of quid. Those cases also make good 18650 chargers because the cells just clip in and are charged by any USB supply/charger.

Or you can get one of those 4-cell waterproof empty boxes for your lights.

http://www.ebay.co.uk/itm/Waterproof-4cells-18650-Battery-Case-Storage-Box-Fit-For-8-4V-LED-Bicycle-Light-/351554147174?hash=item51da429366:g:6YkAAOSw5ZBWJGA1

http://www.ebay.co.uk/itm/Power-Bank-Case-Kit-PCBA-6x18650-Battery-Charger-Flashlight-for-Cell-Phone-DIY-/142054879815?var=&hash=item2113217247:m:mANGLUQRqIuUH7DenLMcDOg

 

[awol]

Thanks for the ideas, my next question was going to ask if anyone has any ideas if the old cells can be used for anything and those are great ideas, I'll get those.

 

[soundwave]

if you get one of them boxes like i have make sure the cells are in the right way round as there is no protection if there not and will melt the springs in side.

you need a 8.4v charger for it 500-1 amp if you dont have one.

 

[anotherkiwi]

You can use your Lipo charger to charge loose cells.

 

[awol]

make sure the cells are in the right way round as there is no protection if there not and will melt the springs in side.

Knowing me, if it CAN happen it WILL happen so I best buy some red and black permanent markers for the cells.

 

[soundwave]

it does say what way up inside the case but i still managed to do it lol.

i just pulled the springs back so touched the cells again and still works.

 

[awol]

Everyone in the house wants one of those powerbank things now I've mentioned it, so what is the easiest way of testing all the cells to identify the best ones?
Is it a case of remove each cell individually and discharge/charge on an imaxB6 ? or can I test each string while still assembled and asume all cells in that string will be the same?

 

[Nealh]

Great life/mileage from that little battery, sadly not loved as much as Eddie's mangled light batteries as you hadn't given it a name. Had you done so it may have found the will to live .

 

[soundwave]

lol the best way is to discharge them at 1amp with a i max charger then you can put them it groups of 4 with the most left in them as you dont want one cell at 1800mah and another at 1200mah.

other wise the pack will fail at the weakest cell in the group.

 

[anotherkiwi]

Everyone in the house wants one of those powerbank things now I've mentioned it, so what is the easiest way of testing all the cells to identify the best ones?
Is it a case of remove each cell individually and discharge/charge on an imaxB6 ? or can I test each string while still assembled and asume all cells in that string will be the same?

Test each one and you want to know internal resistance too. Ones with too high internal resistance you bin.

 

[Deleted member 4366]

I don't think you need to test them. Measure the voltage of each cell group and use the best ones. See how they perform in the power bank. I've got a load of good 1.7 Ah cells if you want some.

 

[awol]

I've got a load of good 1.7 Ah cells if you want some.

Thanks d8veh, I will PM you if I need some.

 

[awol]

Test each one and you want to know internal resistance too. Ones with too high internal resistance you bin.

Internal resistance is something I briefly saw mentioned when first starting out with lipo's but left it there, is this something I will need to monitor on my lipo's when I start using them? Do you monitor the internal resistance on your lipo's?
I've just read something about I would need a resistor and voltmeter and a clear calculating head to work it all out.

 

[soundwave]

http://www.ebay.co.uk/itm/171923199797?_trksid=p2060353.m1438.l2649&ssPageName=STRK:MEBIDX:IT

 

[anotherkiwi]

Internal resistance is something I briefly saw mentioned when first starting out with lipo's but left it there, is this something I will need to monitor on my lipo's when I start using them? Do you monitor the internal resistance on your lipo's?
I've just read something about I would need a resistor and voltmeter and a clear calculating head to work it all out.

Not only Lipo any cell! The best lipo packs are the ones with balanced cells so yes I looked at the resistance and bingo! My weak pack has a cell with higher internal resistance. Your charger should be able to give you the readout of cell resistances. I don't monitor them, if you have imbalance you have a problem. I am nursing my bad battery and it is still working - it stays at storage voltage without budging it just needs to be used immediately after charging otherwise it goes off balance to the order of 0.05V which is a bit above the 0.02V generally tollerated. OK more than twice the amount...

 

[Deleted member 4366]

I bought a special internal resistance meter from ebay for a few quid. Different types of cells have different (a lot) IR, so it's difficult to draw conclusions from one. Capacity measurement is probably the best guide to their health.

 

[soundwave]

I've got a load of good 1.7 Ah cells if you want some.

you got a spare 10.000 i could have for free