Battery loosing power on hills

[Phil]

Hi All,
I have the 750W Motor, 36V 16AH Battery which has been running great for about the past 6 months, but recently has been loosing power up hills. On my regular 10km ride to work I used to power up the hills easily, now the motor overload cut out activates. (at 32V) On arrival home after the 20km round trip there is still about 38V showing. The ride is only one moderate hill of about 2km & the rest is fairly flat. The battery seems to charge Ok up to 41.9V but I can't get the same speed up hills anymore . On the flat all is OK. I'd estimate I've done about 100 charges. Is this the "normal" battery degradation or is there something I can do to get my climbing speed back?

Phil

[Leslie]

Hi All,
I have the 750W Motor, 36V 16AH Battery which has been running great for about the past 6 months, but recently has been loosing power up hills. On my regular 10km ride to work I used to power up the hills easily, now the motor overload cut out activates. (at 32V) On arrival home after the 20km round trip there is still about 38V showing. The ride is only one moderate hill of about 2km & the rest is fairly flat. The battery seems to charge Ok up to 41.9V but I can't get the same speed up hills anymore . On the flat all is OK. I'd estimate I've done about 100 charges. Is this the "normal" battery degradation or is there something I can do to get my climbing speed back?

Phil

The only thing I can suggest is to put the bike onto the charge and leave it on a whole day.  Then unplug and ride for 10 mins charge again and leave on for another day.  See if you can get some energy absorption with a trickle charge.

Then take it for a longer rides and see if range improves.  If it improves a lot see how much range you have lost and repeat the above until range is acceptable. Try to avoid any hard treatment into LVC and nurse the bike back home as to minimize any loss of benefits you may or prolly will not get trying the above..

No harm in trying.

If you see no improvement, one or some your cells are finished.  

Good luck

I hope this helps.

[Phil]

Thanks for the advise, the help in the forums is much appreciated.
No luck after trying this a couple of times. I think a couple of cells may have died during a particularly steep hill climb as this seems to have the point when it all changed. The green battery indicator comes on much earlier than before. (In fact I never saw it before & actually wondered if it was working!) So is it possible to replace the cells myself?
Is there a diagnostic & repair instruction anywhere in the forum, I couldn't find one.
Guess I'll email Tom & see what I can do.


Thanks,

Phil

[Leslie]

Thanks for the advise, the help in the forums is much appreciated.
No luck after trying this a couple of times. I think a couple of cells may have died during a particularly steep hill climb as this seems to have the point when it all changed. The green battery indicator comes on much earlier than before. (In fact I never saw it before & actually wondered if it was working!) So is it possible to replace the cells myself?
Is there a diagnostic & repair instruction anywhere in the forum, I couldn't find one.
Guess I'll email Tom & see what I can do.


Thanks,

Phil

Yes TOM maybe the best course of action.  Battery and BMS's are hard to repair or find faults.  Things can depend on whether it your controller cutting out or the BMS is cutting out.  Current or voltage related.

The controller LVC can indicate current is limited and BMS is failing at the output and the BMS LVC can indicate bad cells and/or BMS connections.  Who knows.

Let us know how you get on hey!

Good luck and be patient.

[dicko]

Hello

Any luck in getting your battery repaired? ive also had the same problem with my battery pack and have emailed Goldenmotor numerous time for a replacement battery (As they are still under warrenty).
Email I sent to GM below.


'Ive had my E-Bike up and running for around 6 weeks now and it’s running well, until the last few times ive riden it.
The first 4 weeks I could ride to and from work on one charge, 9km to work, 9km return.
Last week, I could only ride to work and halfway back, and the battery cuts out.
A few days ago, I could only ride to work 9km before needing a recharge.
Nothing has changed, I ride the same way each time, with hard tyres.
I noticed on the site that a 48v12ah battery should do 50km on a full 48v charge, but im not getting anywhere close to this.
I always use regen breaking where possible, and also peddle aswell.
Is there a way to check if any lithium cells are faulty?'


Any help would be great.

Regards

[Onetom2]

Hello

Any luck in getting your battery repaired? ive also had the same problem with my battery pack and have emailed Goldenmotor numerous time for a replacement battery (As they are still under warrenty).
Email I sent to GM below.


'Ive had my E-Bike up and running for around 6 weeks now and it’s running well, until the last few times ive riden it.
The first 4 weeks I could ride to and from work on one charge, 9km to work, 9km return.
Last week, I could only ride to work and halfway back, and the battery cuts out.
A few days ago, I could only ride to work 9km before needing a recharge.
Nothing has changed, I ride the same way each time, with hard tyres.
I noticed on the site that a 48v12ah battery should do 50km on a full 48v charge, but im not getting anywhere close to this.
I always use regen breaking where possible, and also peddle aswell.
Is there a way to check if any lithium cells are faulty?'


Any help would be great.

Regards

Hi Phil,
My problem was after assembly checked  the charger. It began its flashing red LED.
I searched for an answers.
There is not a single sentence of instructions regarding the Lithium Battery pack Charging protocol.
Seeing the battery state on the twist throttle LEDS red yellow green were ALL 'on' and found the answer to my question on this forum proceeded for a test ride.
Return to base, charger connected I switched on to note the disturbing flashing once again.
It was again by pure accident that I noticed some 4pt text vaguely printed on the charger label.
The two lines headed with a green dot and a red dot explained LED indicators (no mention of flashing, I might add).
By this time I having complained about being registered on this forum and having no tags enabling me to post a question .
I will also mention the connectors were not crimped to the (Bat Pack to controller) power cable, An opened half empty packet of connectors were in the bottom of the box and the light coloured controller case that was supposed to be included with the Rack001 (and screws to attach to bike) was not included. No answer of email sent.
The second trip was a short ride to pick up some screws for another project, approx 10K's at most.
All LEDS still on next day decided to ride 1 14K round trip.
Reach approx 6K's and LEDS extinguished completely.
I cycled back without pedal assistance and even on a cold day was pouring with sweat.

Emailed Tom with complete explanation

First I received this:
What kind of charge you use,36V/2A,or 36V/4A?
Do you have multimeter?
What's the output voltage of your charger?
 
Maybe your charger is broken
Then after sending this:
Thank you for your prompt reply. I have the 36V/2A (1.8A on the label) SSLCO84V42
I have Digital multi meter and got reading 41.7 volts
It was also the first time the green LED came on.
When I plug into battery the Red Led flashes short time then switches off with no LED's illuminated.
Please see enclosed attachment
I think you are correct my charger is broken.
It was in kit purchased from GM order reference number is 3YY684682F782360G
I am still very excited about this electric hub motor can you please replace charger?
I got this:
I think the problem is from the BMS OR cells inside your battery.
What's the voltage of your battery?That position is used to connect plug of charger.
Could you take apart your battery and measure it?
 
Remove the battery end cover containing the charger socket. You will find a printed circuit board (PCB).
It is a battery management system (BMS) which equalizes the charge in each of the cells.
The wire B1 is the one attached to the battery anode. Connecting his professional quality voltmeter to the battery anode and to the other nine wires in succession.

There is one 10-Pin connector on this PCB. (B10 B9 B8 B7 B6 B5 B4 B3 B2 B1)

Measure the voltage between 
the  green wire and other nine wires as below:
 
B1 green wire   to:                              Specification
B2 yellow wire(the second wire)   3.6V  ~   4.15V
B3 yellow wire(the third wire)        7.2V   ~  8.30V
B4 yellow wire(the fourth wire)     10.8V  ~ 12.45V
B5 yellow wire(the fifth wire)         14.4V ~  16.60V
B6 yellow wire(the sixth wire)       18.0V  ~ 20.75V
B7 yellow wire(the seventh wire) 21.6V ~  24.90V
B8 yellow wire(the eighth wire)    25.2V  ~ 29.05V
B9 yellow wire(the ninth wire)      28.8V  ~ 33.20V
B10  black wire (the tenth wire)   32.4V ~  37.35V
 If the voltages are normal, 
then the cells are okay.

Incidentally, 32.4V~37.35V   +  3.6V~4.15V   =  36V~41.5V
Then, measure voltage of the battery 
without BMS (B- and battery anode)  36V~41.5V
with BMS (D- and battery anode)  36V~41.5V
If these two voltages are the same, then the battery pack is okay.
 
Note:If the voltage of any cell is more than 4.15V.I think the cell is overcharger. It can stop BMS and battery work. So you should find out which cell is overcharged.

I am a bit concerned by this development having spent some time scanning associated posts here and found many. where other customers have gone through the same process and found nothing wrong with the battery and nothing else happening to remedy the problem? The other point is the label on the outside of the box stipulates do not remove case. There are two silver labels that seal the front and back of the case, breaking those seals will surely void any such thing as a warranty if it existed, right? There is always the risk of doing damage to the pack or myself. I am considering contacting PayPal. This device is less than 3 weeks old and from what I can see we are not alone in this situation. I certainly don't believe that this device has been over charged unless it was done before it left Shanghai. The short bursts of charging, if at all, and at less than 2 amps couldn't effect anything.   

[Leslie]

Emails to TOM should read like this.

Template below.



Greetings TOM

I have a failure with (insert device here)

I still have warranty for x months.

It is (insert symptoms here)

What should I do?

Thank you.


Template 2.



Greetings TOM

Thank you for your kind reply.

I did what you said.

It works good now.

GM product is awesome now, You Rock.

Thank you very much.



Template 3.



Greetings TOM

Thank you for your kind reply.

I did what you said and still does not work.

I think it is broken.

Can I get it replaced under warranty?

My order number, date of purchase, and details are (insert here).

Please advise.

Thank you

Sorry but his English is adequate to help and knowledge on GM products is sound.

but any eloquence may confuse.

Keep your emails accurate and detailed but keep them short and use common words.  

 (edited for personality sake)

[Phil]

Well, I havent heard from Tom yet, but I'm sure he has a lot of issues to deal with. And yes, I have kept my request in an easy to understand format for non English speakers. I purchaced my kit in August 09, so is probably technically still just under warranty, I'm not concerned too much about it, I'd just like to get it going as good as it did when I first got it. And yes, I had to replace a lot of the wires &  connectors that fell off when I first got the kit, but hey you get what you pay for & it was a minor issue anyway as I have the facility to rewire it.  I'm still happy with the result & know that issues will arise from time to time that need fixing.
I can still manage the 10km to work & 10km back without losing much charge & have hooked up a multimeter to moniter the LVC at 32volts.
So as long as I keep above the 32V LVC it's OK. It does mean I'm going slower up the hills, but I guess I'm getting more exercise! On the flat it's fine, doesn't get to LVC.
My charger seems to be working properly so don't think that's the problem.
Thanks for the info on checking the battery. I've been reluctant to pull it apart untill I have some direction. As advised here by (137537), I think the problem lies with either the BMS or bad cells.
Learning all the time.

Phil

[Phil]

Ok, I've done the test, results:-
There is one 10-Pin connector on this PCB. (B10 B9 B8 B7 B6 B5 B4 B3 B2 B1)

Measure the voltage between
the  green wire and other nine wires as below:
 
B1 green wire   to:                     Actual          Specification
B2 yellow wire(the second wire)   4.19      3.6V  ~   4.15V
B3 yellow wire(the third wire)       8.39       7.2V   ~  8.30V
B4 yellow wire(the fourth wire)     12.58      10.8V  ~ 12.45V
B5 yellow wire(the fifth wire)        16.77        14.4V ~  16.60V
B6 yellow wire(the sixth wire)       20.9      18.0V  ~ 20.75V
B7 yellow wire(the seventh wire)   25.1       21.6V ~  24.90V
B8 yellow wire(the eighth wire)     29.3       25.2V  ~ 29.05V
B9 yellow wire(the ninth wire)       33.5      28.8V  ~ 33.20V
B10  black wire (the tenth wire)     37.7        32.4V ~  37.35V

Both with BMS & without readings are 41.9 V which is the same reading I get each time I recharge.
Could the Magic Controler be the cause of the problem?
Or could it be a temperature related problem, as it's winter here now???

Phil