bring dead battery back to life

123soleil

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Hello,

I bought an electric bike with dead batteries (lead gel cell type). I know that the bike was not used much at all with extended periods gone unused so I am pretty certain that the battery is dead due to bad discharging rather than it being old and worn out.

So my question is, how easy would it be to regenerate the battery and what would be the best method? I see so many methods on youtube... Ideally, I would just use a pulsator but sounds too easy to be true.

(I know it will probably be easier to just replace the battery but I have some free time so I want to experiment :)

Thanks!
 

Fordulike

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Feb 26, 2010
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This is a quote I nicked off the Candle Power forum, and I'm inclined to go with them:

" What usually happens to SLA batteries is they dry up. They have lost their water. If this is the case, it is shot. SLA batteries also HATE to be stored in the "dead" mode. That will do them in too. If anyone has SLA/gel cell batteries on the shelf, CHARGE THEM while in storage on a monthly basis "

Even if you do manage to bring them into play again, they will have atrocious performance and it will sour your e-biking experience.
 
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DAJ

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My neighbour has an interest in mining lamps, he takes lamps that have not been used since the early 1980s and refills them with electrolite from a car battery. Then over a period of days he charges/discharges them untill they achieve an acceptable use time. I have never seen him use so much as a voltmeter but I can assure you those old lamps have astonishing light when recovered, the "Gaffer" lamps have a wide and high beam feature that make me think they would make a good ebike headlamp.

I am sure Gel batterys can't be treated the same but it appears to me Lead Acid batterys are pretty resilient so try a few Youtube ideas, what have you to loose other than the time you already admit you have. Good luck with it :).
 

Fordulike

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Feb 26, 2010
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My neighbour has an interest in mining lamps, he takes lamps that have not been used since the early 1980s and refills them with electrolite from a car battery. Then over a period of days he charges/discharges them untill they achieve an acceptable use time. I have never seen him use so much as a voltmeter but I can assure you those old lamps have astonishing light when recovered, the "Gaffer" lamps have a wide and high beam feature that make me think they would make a good ebike headlamp.

I am sure Gel batterys can't be treated the same but it appears to me Lead Acid batterys are pretty resilient so try a few Youtube ideas, what have you to loose other than the time you already admit you have. Good luck with it :).
Great idea in theory, but a Gaffer lamp will only draw a few amps at most. An electric bike controller can require many more amps to work properly. A duff battery may power the lamp satisfactorily, but not the bike I'm afraid.
 
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Danidl

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My neighbour has an interest in mining lamps, he takes lamps that have not been used since the early 1980s and refills them with electrolite from a car battery. Then over a period of days he charges/discharges them untill they achieve an acceptable use time. I have never seen him use so much as a voltmeter but I can assure you those old lamps have astonishing light when recovered, the "Gaffer" lamps have a wide and high beam feature that make me think they would make a good ebike headlamp.

I am sure Gel batterys can't be treated the same but it appears to me Lead Acid batterys are pretty resilient so try a few Youtube ideas, what have you to loose other than the time you already admit you have. Good luck with it :).
You have nothing to lose but your time. Think of it as a vintage restoration project. Fill the cells back up to the over plates with deionised water ... Not Tap water charge and discharge them multiple times and you will eventually get a response. You may need to break open a covering to get to the cells . You can get special tablets from Halfords which are supposed to rejuvenate cells. Even if you do they will be very poor performance.
Remember an electric bike using SLA batteries is now 4 to 5 generations old. .. . Nicad, MeH, Li ion , improved Li ion have all succeeded it. If you want a working bike it would be better to get the battery case re celled with an Li ion pack and a suitable charger.
 

DAJ

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May 8, 2015
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Great idea in theory, but a Gaffer lamp will only draw a few amps at most. An electric bike controller can require many more amps to work properly. A duff battery may power the lamp satisfactorily, but not the bike I'm afraid.
I get what you are saying but these lamps ran a full shift with capacity to spare, 8 hours day in and day out year after year. Used and abused yet kept their users safe in conditions I can barely comprehend and all of this was 30 - 40+ years ago and today they can be revived. OP should have a play around, perhaps he only needs to go 2 miles not 99 on a charge, lets encourage him not discourage him :).
 

Fordulike

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I get what you are saying but these lamps ran a full shift with capacity to spare, 8 hours day in and day out year after year. Used and abused yet kept their users safe in conditions I can barely comprehend and all of this was 30 - 40+ years ago and today they can be revived. OP should have a play around, perhaps he only needs to go 2 miles not 99 on a charge, lets encourage him not discourage him :).
I agree, but I'd rather a new member gets bitten by the electric bike bug, by riding a bike that's full of zest, rather one that poo poos off the starting line.

Due to lead acid's poor performance on electric bikes full stop, new batteries are the only way ahead.
 
D

Deleted member 4366

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Dead ebike batteries are dead. don't waste time on them. Replacements are not too expensive, but make sure that you get ones that are meant for electric vehicles, not "standby" batteries.
 
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123soleil

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Thanks for all the answers. I just wish they would invent a battery type where you just buy standardized batteries from any store and just stick them in (like changing AA batteries in a radio)... Instead, I have to either build a new pack myself, take my chances with a cheap chinese seller or resort to buying a new pack from the maker at extortionately high prices. In the latter case, I'm probably better off buying a new bike during a sale.

OK, rant over sorry :)
 

soundwave

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Danidl

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I get what you are saying but these lamps ran a full shift with capacity to spare, 8 hours day in and day out year after year. Used and abused yet kept their users safe in conditions I can barely comprehend and all of this was 30 - 40+ years ago and today they can be revived. OP should have a play around, perhaps he only needs to go 2 miles not 99 on a charge, lets encourage him not discourage him :).
There are a number of technical reasons why those older cells might recover better than more recent designs. Originally lead acid cells used sheets of off pure lead.,.,... Similarly to the stuff used in roofing. More recent cells use sintered pellets held together in a wire frame. The Advantage of this later construction is a huge increase in surface area and peak current capacity for the amount of material used. The disadvantage when they are, sulphated there is less recoverable material
S

Eoo
 

Danidl

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There are a number of technical reasons why those older cells might recover better than more recent designs. Originally lead acid cells used sheets of off pure lead.,.,... Similarly to the stuff used in roofing. More recent cells use sintered pellets held together in a wire frame. The Advantage of this later construction is a huge increase in surface area and peak current capacity for the amount of material used. The disadvantage when they are, sulphated there is less recoverable material
S

Eoo
....... By older cells I mean those in the lamps not those in the electric bike, which will in SLA terms be modern.
 

Danidl

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Thanks for all the answers. I just wish they would invent a battery type where you just buy standardized batteries from any store and just stick them in (like changing AA batteries in a radio)... Instead, I have to either build a new pack myself, take my chances with a cheap chinese seller or resort to buying a new pack from the maker at extortionately high prices. In the latter case, I'm probably better off buying a new bike during a sale.

OK, rant over sorry :)
... They do they have and it is the 18650 Li ion cell. The problem is that if they were to be packaged into holders with spring clips and plastic , the overall battery pack would be very much larger and a lot of the power lost in internal resistance between cells. Current practice is to take these cells weld them together and make products for different markets e.g laptops, ebike and ecars...
 

123soleil

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@Danidl yeah I know there are technical limitations but doesn't mean they cant find a standardized format for something bigger than 4.5v

Anything that needs dozens of batteries to be welded or soldered by end user is not going to cut it with 99% of ebike users. They will just throw out the whole bike and by a new one, what a waste!

BTW, this is also why ebike battery packs are so expensive, they practically have to be custom made for each bike. Standardize and the price goes down dramatically
 
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Danidl

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@Danidl yeah I know there are technical limitations but doesn't mean they cant find a standardized format for something bigger than 4.5v

Anything that needs dozens of batteries to be welded or soldered by end user is not going to cut it with 99% of ebike users. They will just throw out the whole bike and by a new one, what a waste!

BTW, this is also why ebike battery packs are so expensive, they practically have to be custom made for each bike. Standardize and the price goes down dramatically
It actually doesn' go down that much the cost of the battery packs is the cost of the cells. There are currently very few actual manufacturers of cells. It is dominated by the few Samsung , LG , Sony Panasonic and probably Varta. These companies sell their product to mainly OEM s who assemble and test battery packs. There are a few generic configurations, called bottle, frog etc from Chinese assemblers and then there are highly customised packages, by the top tier brands Bosch, Yamaha , Panasonic, Kalkoff etc. These are differenciated by more elaborate QA processes.

There is also a growing aftermarket in re celling battery packs even those from the top tier. These recellers work on the cost per cell, number of cells and is virtually the same cost irrespective of the configuration.
Since some 60 cells need to be bonded together they are going to be needed to be packaged together anyway. It just is not feasible for the home user to build battery packs. It is possible as a number of YouTube videos show, but it is not feasible without the proper kit. .. Trust me on this I tried on two occasions to do so, and they worked ... After a fashion..
They do not need to throw the bike away. .. recell the pack using a commercial service!
 

123soleil

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They do not need to throw the bike away. .. recell the pack using a commercial service!
Not trying to pick a fight but you can't just go to a electronics shop and ask them to recell a battery (at least not in my country). Joe Sixpack has no clue what to do with a dead battery and most bike stores will try to sell him a new bike. As proof, people are practically giving away their 5-6 year old ebikes, you can buy them for a pittance. Which is how i got mine :D
 
D

Deleted member 4366

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I just wish they would invent a battery type where you just buy standardized batteries from any store and just stick them in (like changing AA batteries in a radio)
That's probably exactly how it is - standard SLAs that just clip in. If you want to convert to lithium, you just hoik out the SLAs and drop in a complete lithium pack - maybe three or four wires to join.

Open your case up and show us what you have.
 

Danidl

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Not trying to pick a fight but you can't just go to a electronics shop and ask them to recell a battery (at least not in my country). Joe Sixpack has no clue what to do with a dead battery and most bike stores will try to sell him a new bike. As proof, people are practically giving away their 5-6 year old ebikes, you can buy them for a pittance. Which is how i got mine :D
I agree with you . In a way the SLA battery market distorts the way we look at this. The car and leisure markets are very long established and there are a limited range of batteries available. 6v 12v and 24 V , different capacities and two choices deep discharge or high current, even within this there are different connectors an battery shapes.
Contrast this with the mobile bike or laptop battery market. There has been 4 completely different chemistries in almost as many years, each requires different voltage and charging regimes. More significantly each has needed battery management system , which SLA don't.
A more appropriate model might be to look at the electric motor rewind business for alternators, starting motors etc. If you go to a automobile factor they will either sell you a new product or a reworked unit at a lesser price and you exchange your failed unit. This works because these are very standardised.
As the ebike market stabilises this type of reworking will gain market share.
There is one additional wrinkle with ebike batteries..... Safety. Lithium battery of the size used in bikes is subject to transport restrictions.