Two new batteries, now both dead :(

aardvark5

Pedelecer
Jan 25, 2014
212
73
61
ST3 Blurton
I've just had two new 36v 11.6ah dolphin type batteries from what looks like a reputable company (I don't want to name them yet).
The idea is to replace my bottle batteries which are a pain to remove from my two bikes with two dolphins that use a key and lift off.
I am also intending to swap the batteries every week so they both get an equal amount of attention no matter what bike they are on and they will always be removed.
The battery rail comes with two wires like every battery I've ever fitted to other peoples bikes plus my own and obviously red goes to red on the controller and black to black (or does it?).
They are bullet connectors so straight forward.
Also all my parts for both bikes are sourced from Cyclotricity which I've found to be reliable over 6 years.

Last Wednesday I went to work on my hybrid and the LCD display went off and the power cut. This happened a couple of times on my 4.5 mile commute.
Coming home it happened again a couple of times.
On Thursday the same happened going but coming back after about 3 miles the battery went dead so I rang the wife who came to me with the second battery and that got me home.

Today I went to work on my MTB with the 2nd battery and the 4.5 mile was perfect, setting off from work the 2nd battery immediately died and is still dead.

I have two new batteries that have both died on two different bikes.
When the first battery came it looked used because of scratches on it and how it was wrapped gave me the impression it could be reconditioned/used.
The 2nd battery came wrapped the same in a totally different box for a rack battery and it feels like parts are loose in the casing so I thought that could be reconditioned/used.
I've got both batteries on charge now and both are fully charged according to the chargers (green LED).

Any ideas what could be going on?
 

Attachments

Andy-Mat

Esteemed Pedelecer
Oct 26, 2018
896
176
73
I've just had two new 36v 11.6ah dolphin type batteries from what looks like a reputable company (I don't want to name them yet).
The idea is to replace my bottle batteries which are a pain to remove from my two bikes with two dolphins that use a key and lift off.
I am also intending to swap the batteries every week so they both get an equal amount of attention no matter what bike they are on and they will always be removed.
The battery rail comes with two wires like every battery I've ever fitted to other peoples bikes plus my own and obviously red goes to red on the controller and black to black (or does it?).
They are bullet connectors so straight forward.
Also all my parts for both bikes are sourced from Cyclotricity which I've found to be reliable over 6 years.

Last Wednesday I went to work on my hybrid and the LCD display went off and the power cut. This happened a couple of times on my 4.5 mile commute.
Coming home it happened again a couple of times.
On Thursday the same happened going but coming back after about 3 miles the battery went dead so I rang the wife who came to me with the second battery and that got me home.

Today I went to work on my MTB with the 2nd battery and the 4.5 mile was perfect, setting off from work the 2nd battery immediately died and is still dead.

I have two new batteries that have both died on two different bikes.
When the first battery came it looked used because of scratches on it and how it was wrapped gave me the impression it could be reconditioned/used.
The 2nd battery came wrapped the same in a totally different box for a rack battery and it feels like parts are loose in the casing so I thought that could be reconditioned/used.
I've got both batteries on charge now and both are fully charged according to the chargers (green LED).

Any ideas what could be going on?
If a battery slips below a certain minimum voltage, it will not charge anymore, for safety reasons.
You need to measure the actual voltage on each battery and place the values here.
Andy
 

aardvark5

Pedelecer
Jan 25, 2014
212
73
61
ST3 Blurton
If a battery slips below a certain minimum voltage, it will not charge anymore, for safety reasons.
You need to measure the actual voltage on each battery and place the values here.
Andy
1st battery shows 5 blue LEDs (fully charged) but immediately goes off when put on both bikes.
The reading is 45.2 but like I say, I try to turn the LED display on both bikes and both displays flicker and go off.

2nd battery which acts as though it's fully charged on the charger (green light) but shows no blue LEDs on the battery is reading 3.1
 

Andy-Mat

Esteemed Pedelecer
Oct 26, 2018
896
176
73
They both had 5 LEDs showing but I can't for definite say the charger was green.
The charger shows green for two different reasons:-

1) Charge completed, battery at highest volt level (I cannot remember which batteries you have! Sorry!)
2) Battery "refuses" charge for safety reasons, voltage gone too low to be recovered with a normal charger.
There are certain chargers, I have used one, called "Zero Volt Chargers" that can, if the battery is not too far gone, recover it back to normal, but they are difficult to find. The only one I know for sale is from Stark Bikes and this one is only for 36 volt batteries.
See here:-
In the documents with the charger I used they mentioned same type, but for various battery voltages.
Andy
 

aardvark5

Pedelecer
Jan 25, 2014
212
73
61
ST3 Blurton
1st battery is fully charged and shows 45.2 on my multimeter but goes straight off when put on either bike.

2nd battery was fully charged and got me 4.5 miles before dying so I fail to see how going that distance can make the voltage go too low.
Another point, before putting the battery back on to come home, it still had 5 LEDs out of 5 on the battery indicator and also showed full battery on my LED display.
As soon as I started my journey it went about 50 yards before dying.

It doesn't make sense to me unless they were both faulty when I bought them.
 
D

Deleted member 25121

Guest
1st battery shows 5 blue LEDs (fully charged) but immediately goes off when put on both bikes.
The reading is 45.2 but like I say, I try to turn the LED display on both bikes and both displays flicker and go off.

2nd battery which acts as though it's fully charged on the charger (green light) but shows no blue LEDs on the battery is reading 3.1
What voltage do you read across the battery when the charger is connected and indicating that it's fully charged?

Even though the charger indicates that a battery is fully charged try leaving it charging for another 4 hours or so during which time the Battery Management System (BMS) should be attempting to balance the charge stored in the cells.

A high accuracy voltmeter should read somewhere between 41 and 43V across a fully charged 36V battery, you mention 45.2V which is very high, are you using a very cheap voltmeter or the cycle display to read this??

And 3.1V is incredibly low, did you mean 31.0V?
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
9,247
3,538
56
West Sx RH
Forget abut green lights on a charger the only reliable way to make sure a battery is fully charged is by using a meter.
More then 42v isn't good and means the cells have been overcharged this will kill them.
At the mo there's not a lot you can do except get the company to rectify the problem or contact your credit card company to try and resolve the issue.
DO NOT attempt to open or allow anyone to work on the batteries unless at the say so of the vendor.
 
Last edited:

aardvark5

Pedelecer
Jan 25, 2014
212
73
61
ST3 Blurton
A high accuracy voltmeter should read somewhere between 41 and 43V across a fully charged 36V battery, you mention 45.2V which is very high, are you using a very cheap voltmeter or the cycle display to read this??

And 3.1V is incredibly low, did you mean 31.0V?
My multimeter/voltmeter (which cost about £30) is now showing 44.7.
I use it for repairing music gear mostly.
My second multimeter is showing 45 but that was about £10.

The other battery which is showing no signs of life is definitely reading 3.5 now.

Both batteries have been on my hybrid for a very short amount of time, is it possible that a controller or motor could damage them so that when they were put on my MTB they were now faulty?
I'm just clutching at straws.
 
D

Deleted member 25121

Guest
My multimeter/voltmeter (which cost about £30) is now showing 44.7.
I use it for repairing music gear mostly.
My second multimeter is showing 45 but that was about £10.

The other battery which is showing no signs of life is definitely reading 3.5 now.

Both batteries have been on my hybrid for a very short amount of time, is it possible that a controller or motor could damage them so that when they were put on my MTB they were now faulty?
I'm just clutching at straws.
That doesn't sound good, 44.7 / 45V is very high and as Nealh suggests your charger could be faulty and its possible that it damaged both batteries. What voltage do you read across the battery when the charger is connected and indicating that it's fully charged?
What voltage do you get out of the charger when the battery is disconnected?
Did the battery that now gives 3.5V ever give a significantly higher voltage?
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
9,247
3,538
56
West Sx RH
Controller or motor can't do damage to the battery, the battery can cause self harm or blow the controller if polarity is wrong but as you have had the bike working for a few miles that rules that out.
Plug your charger in to the wall socket and take a voltage reading from the chargers dc jack, if it reads more then 42v then that is not good. If it reads 45v that is bad and means you have caused cell damage.
With any dc charging I check charger output often to ensure no change has taken place.
 

aardvark5

Pedelecer
Jan 25, 2014
212
73
61
ST3 Blurton
That doesn't sound good, 44.7 / 45V is very high and as Nealh suggests your charger could be faulty and its possible that it damaged both batteries. What voltage do you read across the battery when the charger is connected and indicating that it's fully charged?
What voltage do you get out of the charger when the battery is disconnected?
Did the battery that now gives 3.5V ever give a significantly higher voltage?
The dead battery (3.5v) reads 40.8v when the charger is plugged in, this was definitely higher because it got me about 6.5 mile.

The high reading battery is reading 45.4v with the charger on.

The charger is outputting 45.4v

The second charger which I haven't used is outputting 45.8v

Just seen Nealh's post - that is not good.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
9,247
3,538
56
West Sx RH
You have over either over charged if that is the case or maybe fried the BMS , try a new pp3 battery in the meter. If the meter battery is old or weak on voltage you will get an eronous reading.
 
D

Deleted member 25121

Guest
The dead battery (3.5v) reads 40.8v when the charger is plugged in, this was definitely higher because it got me about 6.5 mile.

The high reading battery is reading 45.4v with the charger on.

The charger is outputting 45.4v

The second charger which I haven't used is outputting 45.8v

Just seen Nealh's post - that is not good.
No, it's not looking encouraging.

It might be worthwhile trying to measure the charging current with the dead battery, it's internal fuse could have blown.

It's odd that you see the same thing with both chargers, what voltages do you see with the old bottle battery / batteries and how many miles are they still able to deliver?
 

aardvark5

Pedelecer
Jan 25, 2014
212
73
61
ST3 Blurton
You have over either over charged if that is the case or maybe fried the BMS , try a new pp3 battery in the meter. If the meter battery is old or weak on voltage you will get an eronous reading.
Please bare with me, I'm 62 and recently had a stroke so sometimes I panic so sorry for my former readings.

I've put a new PP3 battery in and the battery is reading 41.8v and the charger is reading 41.9v

The dead battery is still 4.5v.
I'm going to leave this on charge to see if anything happens.

So I'm back to square one:
1st battery is at a nice 41.8v but turns off immediately when I put it on either bike.
2nd battery is dead.

Bed time now so thanks everybody and sorry for the wrong readings.
 
D

Deleted member 25121

Guest
Please bare with me, I'm 62 and recently had a stroke so sometimes I panic so sorry for my former readings.

I've put a new PP3 battery in and the battery is reading 41.8v and the charger is reading 41.9v

The dead battery is still 4.5v.
I'm going to leave this on charge to see if anything happens.

So I'm back to square one:
1st battery is at a nice 41.8v but turns off immediately when I put it on either bike.
2nd battery is dead.

Bed time now so thanks everybody and sorry for the wrong readings.
OK, that's looking better.

Leave the first battery on charge for a few hours after the charger indicates that it's full and let us know how it goes.
 

aardvark5

Pedelecer
Jan 25, 2014
212
73
61
ST3 Blurton
OK, that's looking better.

Leave the first battery on charge for a few hours after the charger indicates that it's full and let us know how it goes.
It's still dead after 7 hours :(

So with all the great advice and me eventually putting a new PP3 in the meter it looks like I've been sold two faulty batteries.
Like I said the 1st battery was packed weird and had scratches all over it and the 2nd battery was packed the same in a rack battery box.
I think they are returns that they tried for a couple of minutes and sent them back out.

Thanks
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
9,247
3,538
56
West Sx RH
Phew a sigh of relief aardvark5 on your part, with any strange meter reading not expected a new meter battery is cheap to rule out erroneous readings.
At least on your part it rules out any fault on your side to try and process a refund.

Earlier up the thread ebiker99 asked about your older batteries and whether you have tried them to see that they still work, have you done so ?
If they still work and the bike works then a controller fault can be ruled out as an issue, you can then progress with the vendor or card provider for faulty goods.

Certainly not worth delving deeper in to the batteries at this stage as you will have some warranty or faulty goods procedure on your side.
 
Last edited: