Lead acid battery experts - trying to revive a motorbike battery

[minimutly]

This is just a try it and see, the battery had long been left discharged. I washed it out, pulled some acid from another battery and tried to charge it. It gets up to 13V without pulling much over an amp, all cells bubbling away. When I try a load test one of the cells gives a right pong - rotten eggs smell - hydrogen sulphide? I've tried charging/loading off and on a few times, the end cell still gasses off and the volts drop to 5 or less. I'm guessing the end cell has some coating which is increasing the internal resistance? It would be nice to be able to measure all of them, but it's impossible.
Any experts on here with an idea? I should just buy one I know, it's had its chance really.

 

[Screwdriver]

I have tried pretty much everything to no avail. The closest I got to useable was after spending a few days(!) fiddling with one of those high frequency "reconditioning" devices. Even then, it claimed to have some volts but delivered no amps.

I guess it will depend on the condition of the battery so I have to assume some combination of trickery can recover a battery that isn't too far gone. Like I said though, you only discover that after a lot of faff.

IMO, not worth the effort. Treat yourself to a modern Lithium replacement. They are definitely worth it.

 

[angellonewolf]

most battery are not like 15 years ago where you charge it up over night and its fine again once they drop tomuch there dead and you have to replace

 

[Greeves246]

Bike batteries usually get overcharged by car chargers, and plates get buckled and short out. Max charge rate should be 10% of the batteries rating. Gassing rate for lead acid batteries is 14.8 v. I refused warranty claims on dozens of new batteries that had buckled plates from overcharging when I was a rep.

 

[Screwdriver]

Bike batteries usually get overcharged by car chargers, and plates get buckled and short out. Max charge rate should be 10% of the batteries rating. Gassing rate for lead acid batteries is 14.8 v. I refused warranty claims on dozens of new batteries that had buckled plates from overcharging when I was a rep.

Oi. I resemble that remark!

Got sick and tired of so called "smart" chargers failing to do a damned, thing a fair few of my bike batts over the years have had to endure a brutal, simple car charger stuffed up them.

So, err, guilty as charged...

 

[MetalMonkey]

You could try and desulfate it. Various methods out there

Another trick I've seen but never tried is to reverse the polarity - but I'd only do that when its scrap and you have nothing to lose and plenty of time to waste.

 

[addjunkie]

Save your effort, buy a new un

 

[charlysays]

Some guy on YouTube shoved a welder on one in a video I watched recently and it went went from dead to holding out on a load test. I haven't watched the follow up as he was going to use it in his truck for a month to see how it did. Sounds potentially quite dangerous so do not try it is what I will say.

 

[brightspark]

its sha,gged out buy a new one

 

[Onoff]

I recovered a dead mower battery.

First empty it of acid into a safe container.

Clean with bicarbonate of soda solution about 10% bicarb. That reacts & cleans all the crap off the plates. It'll fizz a bit etc. Tip on it's side and hose out with clean water.

Then fill with 12% epsom salt solution and trickle charge for 24 hours.

Got to about 13V and started the mower no problem. That was with the epsom salt solution still in and no acid.

Keep meaning to put the original acid back in but never have...

TK Maxx or Super drug etc do epsom salts or Amazon of course.

 

[Onoff]

Cheap enough to try surely?

+

If it doesn't work you can still have a nice relaxing bath.....

 

[minimutly]

I'll try the Epsom salts, bloody minded learning cycle, it's been trickling at or around an amp for a week...

 

[Screwdriver]

Epsom salts don't work. They are a hack method for removing the build up from sulphation. Better ways of doing that, ways that wouldn't ruin the life of the battery (if it still had any).

 

[Ross365]

Some years ago, I bought a "pulsator" unit which is intended to de-sulfate (correct UK spelling is now with an f !) batteries. This produces voltage spikes which are about 16V but only last a tiny fraction of a second, but there are very many pulses per second. This has proved to work very well on (some) full size car batteries (but takes some days), but for obscure reasons, it has never worked at all on small lead acid (~5Ah) batteries. My general feeling is that with old lead acid batteries, you have to value your time very cheaply to justify trying to rejuvinate them.

Re "smart chargers", I'm retired, and have two cars, and they don't get used enough in winter to keep the batteries well charged, and a couple of years ago a friend recommened getting a CTEK smart charger, which can be left connected and will stop charging when the battery reaches around 14.8V. Quite expensive, but I've been really glad I bought it; "connect and forget". Prior to the CTEK, I had a cheap smart charger from eBay; I was really unhappy I bought that as it quickly failed, and "boiled" a battery to death .

 

[Ubique]

... which is intended to de-sulfate (correct UK spelling is now with an f !) ...

No it's not!

For many years there has existed a difference in the spelling for the name of element number 16 with the symbol S. British English spelt it "sulphur" while North American English used the phonetic spelling "sulfur". In the late 20thC, the International Union of Pure and Applied Chemistry (IUPAC) decided that the single spelling of sulfur was prefered. Throughout this course, the British spelling and its derivatives have been used, but the IUPAC version is equally acceptable.


Strangely enough, guess where the city named Sulphur (and not Sulfur) may be located? It is located in the State of Louisiana in the United States, which just shows how illogical the spelling of words may be!

sulphur vs. sulfur

spelling, and regional differences

www.grammar.com

In English it's Sulphur, if you want to use simplified english, it's sulfur - ironically dumbed-down for academics worldwide...

 

[bricol]

Over 40 yrs of playing with lead acid batteries (used to use one as a portable power supply for charging R/C car batteries at race meetings) tells me you are wasting time and effort. Put it in the "weigh-in" pile and buy a new one.

If it's for a little used vehicle, then as above, buy a CTEK charger - that's kept three of my little used batteries, two of which were dirt cheap Euro-carparts things, working well for the last decade or more.

Worst thing to do with any lead acid battery from my experience - let it go flat and leave it flat. Going flat, but charging before it's left too long, and then using it, seems to work okay.

But if one dies between parking the car and then trying to restart it, excepting some car fault that flattened it, then the only way to be sure it won't be midnight and won't start is a new battery.

 

[Bdog507]

Good morning All.


A lot depends on whether a battery is just flat, or flat due to a fault. My rule is that if it doesn't charge fully, or drops to below 11 volts on cranking the engine it's had it.
Sometimes customers insist that I try to recover a dodgy battery. I tell them it's not usually possible.
Most likely they've seen the claims for these so called smart chargers.
Undoubtedly these chargers give a good battery a decent charge, & will remove light sulphation, but I've never seen one recover a bike battery that's gone below 10 volts.
As Ross365 says, sometimes they do work on car sized batteries, but not on small ones.
I've also had it where the charger indicates that the battery is good, but it'll only crank the engine for two turns before giving up the ghost.

One good thing about lead acid batteries, as opposed to the more modern sealed types, is that they'll take more abuse.
Many years ago when dispatch riding on my trusty Yamaha 900 I got back late from a run to Suffolk.
The following morning the neutral light resembled a half dead Glow worm. Inspection revealed that the regulator had gone & the battery had been boiled dry.
I filled it with distilled water & much to my surprise it took a charge. After fitting a new regulator it started the bike & was charging nicely.
As it was only a month old I hoped it may last a couple of weeks. Errrr try 2.5 years!
By which time I had started my bike repair business.
I changed it because it was struggling to start my 900 on cold mornings. I kept it in the garage as a 12 volt source for things like timing lights & so on.
6 months down the line a customer came in on a 750 Kawasaki with a split battery. After a baking soda wash I fitted my old 900 battery to his bike so he could get home. He got about 5 months out of it.


Cheers.


Stewart.

 

[minimutly]

Epsom salts don't work. They are a hack method for removing the build up from sulphation. Better ways of doing that, ways that wouldn't ruin the life of the battery (if it still had any).

Thanks to all for contributing, I think we're all agreed it's had it, but I was hoping to revive it enough so avoiding buying a new one for a bike that most likely isn't going anywhere for a while.
So what's this "better way" of de-sulphonating it then @Screwdriver?

 

[Morris]

No it's not!

sulphur vs. sulfur

spelling, and regional differences

www.grammar.com

In English it's Sulphur, if you want to use simplified english, it's sulfur - ironically dumbed-down for academics worldwide...

Ignore this. Use the correct old spelling. Brimstone.

 

[Seadog]

A point that hasn't been mentioned ( I think), is that as the separators break down they leave a deposit at the bottom of the battery which is a discharge path.

My physics teacher still had the original 10 year old battery in his Mini because, every year, he charged it, drained it, and thoroughly flushed it with distilled water, before refilling with fresh sulphuric.