poor result from new battery

mga

Finding my (electric) wheels
Jul 14, 2010
8
0
I have an ezzee cadence cycle and have recently (last month) purchased a new chinese battery 36v 15 a fitted to the cycle carrier i charged battery end went 5 miles in green and yellow light mode before battery failed i then recharged battery took 2hours to fully recharge and then went out again same result red light never appears. Switching on then off brings a positive result until yellow light goes on and then drive stops and light next to key goes out. Light next to key flashes 7 times when battery charge is at an end. Any help would be appreciated ken
 

flecc

Member
Oct 25, 2006
52,809
30,379
The battery is supplying a slightly too high voltage Ken, that's what the 7 flashes indicate. It means the fully charged voltage is over 44 volts roughly and the safety cutout of the controller has stepped in.

I can't offer any opinion on the battery quality obviously, but it seems to be unable to deliver enough current for your powerful motor. Try charging a bit short of the usual full time to ensure it doesn't reach beyond 43 volts fully charged and then try it on the bike.

If you can't do that because it's too high voltage, leave it for a day or two to lose the surplus before riding.
.
 
Last edited:
D

Deleted member 4366

Guest
Could you measure the battery voltage fully charged straight of the charger and again when it cuts out? How did you wire the new battery to the controller?

I've heard of some BMSs that take their power from a single cell so that if you leave it for a long time, one cell would be out of balance, but I think the BMS is supposed to sort that out when you charge it. Maybe a couple more charge cycles might fix it.
 

banbury frank

Banned
Jan 13, 2011
1,565
5
Battery

I don't know why you help these idiots They bought a cheap import tell them ask the supply in china Ha Ha Ha


Frank
 
D

Deleted member 4366

Guest
Nearly all these sort of things come from China one way or another. I don't know whether you know, but there's hardly any British manufacturing left.
 

Synthman

Esteemed Pedelecer
Aug 31, 2010
417
0
Oxford
I should really have made a new thread for this, but I was wondering if the fully charged voltage on a LifePo4 36v would be too high for a bike like mine and cause problems? I'm looking at getting a 15ah one later this year.
 

banbury frank

Banned
Jan 13, 2011
1,565
5
Battery repair

Hi I am up early this morning sorry every body for my comment long day

I think I understand the problem we need a good UK supplier

if one was available we would all pay a premium for UK support

I understand you had no option to get your battery from china

I think you should bye a new controller I have seen one that takes

36 v and 48 volt http://www.ebikes.ca/store/photos/C3635-NC.jpg

cost about $200 and yes you will have to pay vat and duty as the use FedEx

This is a awesome controller



Frank
 

flecc

Member
Oct 25, 2006
52,809
30,379
I should really have made a new thread for this, but I was wondering if the fully charged voltage on a LifePo4 36v would be too high for a bike like mine and cause problems? I'm looking at getting a 15ah one later this year.
LiFePO4 cells are a slightly lower voltage than the usual lithium types, but manufacturers sometimes compensate for this by using more cells in series. That can result in rather high voltages when fully charged. Many controllers are fairly tolerant of this, but the eZee one that the original questioner asked about has strict limits, 32 volts low and 44 volts high, both with a tolerance of plus or minus a half volt. Basically designed for their specified batteries of course.
.
 

mga

Finding my (electric) wheels
Jul 14, 2010
8
0
many thanks for your prompt and helpful suggestions and suplimentary data. I conducted a test of the battery under a 10 amp load ( electric fire element )and found that after 17 minutes the battery cut out having dropped to34 volts this is in line with my experience with the battery attached to the cycle i am therefore returning the battery under guarantee to the supplier in china one or more cells are faulty or the bms is cutting in too soon i think it is the former thanks to all for help. I would mention however that i object to being called an idiot by frank just because i am unable to afford an english battery needed to help my medical needs to continue cycling
 

banbury frank

Banned
Jan 13, 2011
1,565
5
Battery repair

Hi I did apologize to the forum but I will tell you somthing else I dont think you can return the goods to china as I have been told right or wrong ther is a large import duty into china and the companny would need to pay that

and the will just refuse to have anything to do with it

If you complain enough they will probably send you another one if you pay the shipping costs


Frank
 

NRG

Esteemed Pedelecer
Oct 6, 2009
2,592
10
You insulted 'mga' not the forum...
 

rog_london

Esteemed Pedelecer
Jan 3, 2009
764
2
Harrow, Middlesex
I'm an engineer, and the thought of buying a generic battery from China fills me with dread. I think I'd apply an exception to Mr. Ping, who is well regarded as supporting his product, but in general you have no protection at all if something goes wrong or the product doesn't do what you expect.

In China they produce almost identical products for different world markets, but the quality can vary from excellent to awful - not to mention dangerous. Even the same production facility can do this in parallel - rubbish to be sold cheaply in 'third world' countries being manufactured alongside top-quality kit designed to be sold at a premium in the West. I've seen it in domestic electrics - you buy Chinese made light sockets in Ghana (a country I have considerable dealings with) and they look fine but they're nasty, and the plastic soon becomes brittle and falls to bits in the heat. What looks identical but bought here - also made in China - is of high quality, and the Ghanaians have learned that if they have the contacts and can afford it it's better by far to import from the UK and pay double the price.

Getting back onto the subject of ebike batteries, it's tempting to pick up a bargain rather than pay £500 for something which you know will work and carries a decent warranty. I'm surprised we haven't heard (yet) of anyone having their house set on fire because a nasty battery has internally shorted itself. I know there are many on here who have bought batteries from China and not had any problems, but there's a significant risk, and NO WARRANTY other than the goodwill of the supplier, who may or may not send you a replacement if you have a problem.

To repeat what has been said before, ebike batteries are a design nightmare, because there are weight and size constraints which mean that what you have to use gets abused from day one, and that's reflected in what you pay and the relatively short life. You can't avoid applying excessive discharge currents in order to get decent assist when you need it - on hills - and if you have a borderline illegal bike the problem becomes much worse as a relatively small increase in top assisted speed carries a big penalty in battery discharge current.

I wouldn't be so blunt as to call someone who buys a battery direct from China 'an idiot' but I can see Frank's point. If anything, the more you know about the issues involved, the more cautious you become, and it can be naive to buy a dangerous pig in a poke with little chance of redress.

Rog.
 

Old Timer

Esteemed Pedelecer
Dec 5, 2009
1,279
12
I'm an engineer, and the thought of buying a generic battery from China fills me with dread. I think I'd apply an exception to Mr. Ping, who is well regarded as supporting his product, but in general you have no protection at all if something goes wrong or the product doesn't do what you expect.

In China they produce almost identical products for different world markets, but the quality can vary from excellent to awful - not to mention dangerous. Even the same production facility can do this in parallel - rubbish to be sold cheaply in 'third world' countries being manufactured alongside top-quality kit designed to be sold at a premium in the West. I've seen it in domestic electrics - you buy Chinese made light sockets in Ghana (a country I have considerable dealings with) and they look fine but they're nasty, and the plastic soon becomes brittle and falls to bits in the heat. What looks identical but bought here - also made in China - is of high quality, and the Ghanaians have learned that if they have the contacts and can afford it it's better by far to import from the UK and pay double the price.

Getting back onto the subject of ebike batteries, it's tempting to pick up a bargain rather than pay £500 for something which you know will work and carries a decent warranty. I'm surprised we haven't heard (yet) of anyone having their house set on fire because a nasty battery has internally shorted itself. I know there are many on here who have bought batteries from China and not had any problems, but there's a significant risk, and NO WARRANTY other than the goodwill of the supplier, who may or may not send you a replacement if you have a problem.

To repeat what has been said before, ebike batteries are a design nightmare, because there are weight and size constraints which mean that what you have to use gets abused from day one, and that's reflected in what you pay and the relatively short life. You can't avoid applying excessive discharge currents in order to get decent assist when you need it - on hills - and if you have a borderline illegal bike the problem becomes much worse as a relatively small increase in top assisted speed carries a big penalty in battery discharge current.

I wouldn't be so blunt as to call someone who buys a battery direct from China 'an idiot' but I can see Frank's point. If anything, the more you know about the issues involved, the more cautious you become, and it can be naive to buy a dangerous pig in a poke with little chance of redress.

Rog.
Rog

And so the rip off merchants will continue to charge the extra premium:rolleyes:

You can only go by your own experience and my £180 15Amp 36V battery from China certainly drives my Aurora along at a decent pace for plenty of miles. I did get the nod from another buyer that all was well.

BTW if he wants to post on here he will tell you about his Ping disaster which tells me that what ever you pay you take a chance;)

BTW Frank! you aint gonna be making many friends on here with that attitude matey.

Dave
 

banbury frank

Banned
Jan 13, 2011
1,565
5
Dead battery

Reply to rogs remark he is the one who recommended Mga to bye the battery for a ebay site with a 95 percent feed back £188 means without deliver charges the Battery bms and charger cost about £145

Why don't you help Mga with his battery you recommended

Or give him a refund If not follow your own Advice on your postings



Frank
 

rog_london

Esteemed Pedelecer
Jan 3, 2009
764
2
Harrow, Middlesex
Reply to rogs remark he is the one who recommended Mga to bye the battery for a ebay site with a 95 percent feed back £188 means without deliver charges the Battery bms and charger cost about £145

Why don't you help Mga with his battery you recommended

Or give him a refund If not follow your own Advice on your postings

Frank
Huh? I never did! Where did you get that idea from? Probably from the bottom of a beer glass - again!

Rog.
 

onmebike

Esteemed Pedelecer
Jan 3, 2010
499
1
West Essex
many thanks for your prompt and helpful suggestions and suplimentary data. I conducted a test of the battery under a 10 amp load ( electric fire element )and found that after 17 minutes the battery cut out having dropped to34 volts this is in line with my experience with the battery attached to the cycle i am therefore returning the battery under guarantee to the supplier in china one or more cells are faulty or the bms is cutting in too soon i think it is the former thanks to all for help. I would mention however that i object to being called an idiot by frank just because i am unable to afford an english battery needed to help my medical needs to continue cycling
Bms sounds ok if cutting at 34volt. Not sure who you purchased from but if Daoji666 on ebay you'll need get a returns number before shipping back. The returns details are on the ebay listing.
I've dealt with this guy several time's and don't think you'll have any problems. Unfortunately its an inconvenience you could do without.
Even the best battery's have failure's, you've just been unlucky but I'm sure it will get sorted.