sudden battery death or charger malfunction

nab

Pedelecer
May 10, 2010
60
0
Hello all

I've got an Ezee Torq (great bike btw) which I bought second hand.

The battery was a couple of years old when I bought it and I was using it a lot over the summer that I've had it (16 miles a day with a couple of steep cornish cove roads thrown in).

One day it suddenly stopped being able to charge. When I plug it in the charging light will come on the charger but then after approx one minute the charged light will display on the charger.

Do batteries suffer this sort of sudden death syndrome? or could it perhaps be a problem with my charger?

There is still a bit of battery left in it for local trips etc so I want to put off the outrageous £500 replacement cost :( for a little bit.

Any thoughts or help much appreciated. :D

Cheers

Neil
 

JuicyBike

Trade Member
Jan 26, 2009
1,671
527
Derbyshire
Have you checked the fuse on the battery Neil?
 

nab

Pedelecer
May 10, 2010
60
0
well, i unscrewed it and i can see the fuse through the glass tube. if the fuse is blown i assume it would look snapped?

i think it looked ok. i will take a closer look at it later though.
 

jerrysimon

Esteemed Pedelecer
Aug 27, 2009
3,292
112
Cambridge, UK
Nab if you have a meter you can do a continuity test on the fuse.

I have DIY A123 battery packs and recently, after two years, 2500 milles and 500+ charge cycles, I have had two cells fail in succession. I have swapped them out but it will be intersting to see if the other cells follow their whimpy partners.

I would have thought that the battery would slowly decay in terms of the distance it lasts rather than suddenly failing.

PS I am sure your could find an alternative to the stock £500 battery, though it may require some DIY skills to put it into the old case.

Regards

Jerry
 
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nab

Pedelecer
May 10, 2010
60
0
I have a multimeter test kit. never used it before though. good opportunity innit?
 

jerrysimon

Esteemed Pedelecer
Aug 27, 2009
3,292
112
Cambridge, UK
Yes :D

Turn the central dial to the continuity test shown here



It will read 1 when the prongs are apart and 0 ish when you touch them together. So if you put them across the fuse and it stays at 1 you will no the fuse is knackered :p

Did you see the link above for the replacement battery ?

Regards

Jerry
 
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nab

Pedelecer
May 10, 2010
60
0
Thanks so much Jerry. i will try the multimeter when I get home.

I will also look at the link for a replacement battery when I get home (it is filtered at work for some reason!)
 

jerrysimon

Esteemed Pedelecer
Aug 27, 2009
3,292
112
Cambridge, UK
NP.

They probably filter Ebay as that is what the link is to, a new Li Ion 36v 10Ah inner for existing battery cases.

I am the ICT Manager at work and we don't filter web access at work, trusting people not to abuse it.

Regards

Jerry
 

Scottyf

Esteemed Pedelecer
Feb 2, 2011
1,403
-1
I am the ICT Manager at work and we don't filter web access at work, trusting people not to abuse it.
Like our IT department. Although i'm abusing it right now.
Although I get on very well with our IT dept I think its better its unfiltered. Mainly to allow me 2 mins to relax and post rather than run out of focus on other tasks that use the pc.

Lets us all know how you get on with the battery. It will be a simple fix hopefully.
 

nab

Pedelecer
May 10, 2010
60
0
i didn;t know you could reuse the case. that might save a few bob.

my diy skills aren't that hot though....always keen to have a go at things though.
 

nab

Pedelecer
May 10, 2010
60
0
the fuses check out ok. i checked the one on the charger too.

after about one minute of charging the light goes to green as if it is fully charged (I know it's not!) and the fan on the charger stops whirring.
 

jerrysimon

Esteemed Pedelecer
Aug 27, 2009
3,292
112
Cambridge, UK
Ok thinks......

I wonder if the charger is faulty ?

Some of these batteries have internal fuses as well. Maybe time to open up the case. Remember though these things carry a lot of current.

Regards

Jerry
 

shemozzle999

Esteemed Pedelecer
Sep 28, 2009
2,826
686
the fuses check out ok. i checked the one on the charger too.

after about one minute of charging the light goes to green as if it is fully charged (I know it's not!) and the fan on the charger stops whirring.
What voltage is the charger set to? Is it shown on the charger case? - can you measure the voltage on the output connector with a meter - I think it should be about 29.4V to give 4.1v / cell.
 

nab

Pedelecer
May 10, 2010
60
0
What voltage is the charger set to? Is it shown on the charger case? - can you measure the voltage on the output connector with a meter - I think it should be about 29.4V to give 4.1v / cell.
on the case it says

input 115V/230VAC
60/50Nz 1.5/0.9A
output: 36VDC/2A

I just tried a different kettle lead and no difference.
 

jerrysimon

Esteemed Pedelecer
Aug 27, 2009
3,292
112
Cambridge, UK
What voltage is the charger set to? Is it shown on the charger case? - can you measure the voltage on the output connector with a meter - I think it should be about 29.4V to give 4.1v / cell.
Yes good idea. Turn your multimeter to DC 200V or at least enough so you can measure 36V (see the previous picture) and then switch on your charger. Move the battery away i.e. disconnect it from the charger as we don't need that at the moment. Now plug your charger in to the mains and on the OTHER end where it plugs into the battery check the voltage coming out of it. Be carefull NOT to touch the two prongs together. It should read 36V or there abouts.

Don't worry about getting the prongs on the right + or - terminals as the voltage will just read -36v if you get it the wrong way round. But as I said be carefull not to touch the tester prong tips together (whilst they are on the charger terminals) or short one across the plug pins that connects to the battery.

This way we can eliminate the charger as a possible fault.

Next we can test the voltage of the battery but we need to be very carefull and not short it as it can put out a lot of current :eek:

Maybe we should be putting an "at your own risk" warning here ?

Regards

Jerry
 
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jerrysimon

Esteemed Pedelecer
Aug 27, 2009
3,292
112
Cambridge, UK
sounds scary :eek:

how do you ensure that you don;t get fried then?

neil
PS if you are asking this question then its possibly not a good idea to start taking the battery apart.

Regards

Jerry
 

shemozzle999

Esteemed Pedelecer
Sep 28, 2009
2,826
686
Oops, see you have a 36v system, ignore the 29.4v, thats the charge voltage on a 24v 7 cell battery, but you still need to meter the charger and battery voltages - make sure you switch the meter to a suitable range to read 36v.
I've also assumed the battery is Li-ion as it is two years old, but the charger voltage reading will give a better idea.


May be worth having a look here:

Charging Lithium-Ion Batteries
 
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banbury frank

Banned
Jan 13, 2011
1,565
5
Hi Nab

I suspect BMS or a wire off in the pack Battery cells don't just fail they just decrease in range

Where are you

Frank
 

nab

Pedelecer
May 10, 2010
60
0
Yes good idea. Turn your multimeter to DC 200V or at least enough so you can measure 36V (see the previous picture) and then switch on your charger. Move the battery away i.e. disconnect it from the charger as we don't need that at the moment. Now plug your charger in to the mains and on the OTHER end where it plugs into the battery check the voltage coming out of it. Be carefull NOT to touch the two prongs together. It should read 36V or there abouts.

Don't worry about getting the prongs on the right + or - terminals as the voltage will just read -36v if you get it the wrong way round. But as I said be carefull not to touch the tester prong tips together (whilst they are on the charger terminals) or short one across the plug pins that connects to the battery.

This way we can eliminate the charger as a possible fault.

Next we can test the voltage of the battery but we need to be very carefull and not short it as it can put out a lot of current :eek:

Maybe we should be putting an "at your own risk" warning here ?

Regards

Jerry
i've done it....tentatively and nervously......and i'm still alive :D

it measured 41.6. that's over 36V. i assume that's within tolerances?