Author Topic: unusual car battery shelf life  (Read 3613 times)

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dnix71

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unusual car battery shelf life
« on: January 22, 2017, 12:36:34 PM »
I have a coworker from the Caribbean whose sister bought a 2004 Toyota new and left it here for local transportation when she is stateside.
She had intended to take it home, but family illnesses and other needs prevented this. The car is now being driven by her brother, my coworker, because his 2006 Mitsubishi is in much worse shape. Otherwise is just sat and was started once a month to keep the battery topped off.

Friday he complained that the battery wouldn't start the car that morning and asked me to check it out before he went home. There was dry corrosion on the terminals and a little cleaning and all was well again. The alternator was putting out in the high 13's, and the caps were removed and the water checked and it was full.

Then I asked how old the battery was and he said it came with the car. The battery even had "Toyota" in bold letters across the top label. That would make that battery 14 years old. The year and month dots were never removed at installation, so I can't be sure.

If that's true, then it must be something about the way lead acid batteries are charged and discharged that ages them, not time itself.

DamonHD

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Re: unusual car battery shelf life
« Reply #1 on: January 22, 2017, 01:10:04 PM »
Hi,

I doubt it's either/or, but a complicated combination.

Being started once a month to keep the battery topped off sounds like (a) relatively careful maintenance and (b) very light use.

Plus in the Caribbean the capacity should be fine with reasonable ambient temperatures, unlike (say) my poor bank currently near freezing in a shed:



Rgds

Damon

tanner0441

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Re: unusual car battery shelf life
« Reply #2 on: January 22, 2017, 03:32:49 PM »
Hi

I have an RV fitted with two batteries. An AGM 95Ah as a house battery and a cheap flooded lead acid for the engine.

The house battery is about 6 years old and as an expensive I am not surprised it still returns over 90% state of health.

The engine battery is a budget flooded lead acid and is some 7 years old, and last year after the battery charger conditioner was switched off accidentally dropped to a level which wouldn't even light the dash lights. It did recover and shows a state of health of 87%

I think the reason is: The charger conditioner it is a three step unit for an hour after switch on it pulses the battery at just over14.8V then for 3 hours it drops to a steady 14 V then drops to a level just cycling as the battery at a steady 13.2 to 13.8 V. It has a maximum current of 3.8 A. As an RV it only gets used a few times a year. Which would tend to confirm the statement about careful maintenance.

They are hard wired into the vehicle so as long as the shore power is connected the conditioners are running. I periodically disconnect the power for 24 hours or so to allow the batteries to stabilize before testing.

Brian




george65

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Re: unusual car battery shelf life
« Reply #3 on: January 22, 2017, 03:44:28 PM »
 My Father had a car in his wrecking yard  I saw between Christmas and New year.
It was very Clearly Marked as being from 2009 which made it just over 7 years old.  It still started the car.
That's the oldest  car battery I have ever seen. I usually think I'm getting a good run if I get one that.ls done 3-4 years.

Many cars here now have the battery in the boot, not because of Space limits in the engine bay but because of heat.  A mate had a High performance car  ( Pontiac GTS? in the states) and went through 5 batteries in the 4 years he had it. They replaced the batteries without question as it was a common problem. The next model he got of the same car had the battery in the boot so they could prevent the problem.

 I haven't bought a new battery in about 20 years.  I get 2nd hand from the wreckers for $20-30 and still get the same 3-4 Year life out of them on average I got from $120 brand new ones.  Worst I ever got from a used battery was 15 months but I only paid $15 for that one as the guy said it was a bit old when I bought it.  For the price paid and the service I got out of it, not complaining.  We see them come into the yard that are pretty new but because the things can sit months at the auctions before we get them and often when you put a battery in you find the lights are still on or the damage meas a door light or boot light is activated, the batteries are dead flat.  They may only be months old but you charge them up ) If they will take a charge ) and then test them and they are cactus.  Sitting round flat with maybe a load still on them just kills them. It's good when they come in and are disconnected because you know they are still probably going to have some charge and have a better chance of surviving.

I always keep a spare around now. Always something I need a battery for anyway and I'm never stuck when one does die.
I also have one of those Lithium battery pack things that has a torch, USB ports and can power my laptop for a few hours as well. One of the best things I own.
I bought them for my Dad for starting cars instead of having to lug a trolley with a battery all around his very large yard.  Thing starts my 4.2L Diesel Truck without a problem at all including giving the glow plugs a hit.

My father has started 10 cars at a time with it and started 8 of them twice and the thing was still fine.  We both reckon it is one of the best things we have ever had.
I was told by the guy I bought it from that they had just completed a trial with some Government busses where they installed a pack and a change over switch. When the battery on the busses went flat they just changed over to the start pack which he said was about half the size of a normal car battery and they could start the bus right up. They were also doing a trial for tour Coaches and had orders from companies even before the testing had ended.

It will be interesting to see which way they got with car batteries, Lithium derivatives or super caps I have seen talk of.  Cost, size and weight will all no doubt play a part. Safety may be a concern with Lithium. 
I had a stupid Bimbo run into the back of me last year and something shorted under the bonnet. After the steam from the radiator had gone, the smoke started. It was amazing how people panicked. I literally had people trying to drag me away from the thing by the arm while screaming  " It was going to blow".  I'm standing there next to the thing shaking my head thinking how clueless they were despite their obvious PhD's in television  watching education.  Of course the main fuse blew or the wiring burnt off and the smoke stopped without incident but there wasn't another person around within 25M by that stage. Her POS Mouse car Toyota was a write off anyway ( drove my Subaru away without any structural damage at all) so I would have been happy to see the other thing burn but I knew it wasn't going to.

With the cars we see come into the yard, it's obvious there is no really safe place to put a battery that could give off a toxic gas if damaged. You can certainly place it where the incidence of damage is lower, but then again the damage does not have to be severe to get a hit anywhere. We see Lots of Subaru's hit in the middle and under the floor because people push too hard in corners and loose grip sending them up over gutters and gardens etc. 

dnix71

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Re: unusual car battery shelf life
« Reply #4 on: January 22, 2017, 05:51:49 PM »
I was in Walmart last week to buy a tire and saw a clerk stocking batteries with a 5-year warranty. Most car batteries here in south Florida only last 2 or 3 years. I have had more than a few that died after a year and a half.
So I asked the clerk what Walmart had discovered that would make a car battery last 5 years and he began to laugh. He said they still failed after 2 years on average.

Heat kills batteries, so unless it's mounted somewhere other than under the hood it won't last long in a hot climate like south Florida.

I have had 2 tires fail prematurely on my Toyota Corolla because someone installed an oversize muffler without a proper heat shield. 2 tires in the same position dry rotted and delaminated on the inside and the brakes on that side leaked because the muffler was installed too close without a heat sheild. After the second tire failed I took a closer look and added a piece of sheet metal to block the muffler heat.

clockmanFRA

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Re: unusual car battery shelf life
« Reply #5 on: January 23, 2017, 12:01:02 AM »
My brother bought a new Toyota (big European 1800cc petrol saloon) in 1998, and yes the original battery is/was still on it 2016.

Interestedly the battery is very large compared to the new types, and my bruv insists on carefull maintenance. But the Toyota interior electrics were poor, sun roof, interior lights etc never worked properly.

Any ways, I end up with it and push the car as far as possible. Sadly here in Europe we have some barmy laws that reckon that at a certain age then there must be corrosion. So getting it through its 2 yearly Controlle technique, MOT, Government inspection, becomes an expensive task even though the car is mechanical sound, (good emissions results) and structural sound bodywork, (no holes etc).
Also Toyota used a synthetic rubber ring seals on the water coolant system that after 20 years seem to just perish, so new seals required on the complicated pump system. Just becomes uneconomical to repair.

Here in France my mate Dimitri, Eco warrior type, (profession wood specialist with chainsaws, forest tractors, cranes etc, a Volvo nut), knows a guy at our local ship port, 'Le Havre'.
 
Filled in the official scrapping Government forms, and Dimtri drives the Toyota it to the Port with buckets of water, onto a Chinese Freighter that drops it off in the Cameroon in Africa, looks like a little crew side line, locals will repair the coolant system and the Old Toyota and its battery lives on.
Everything is possible, just give me time.

OzInverter man. Normandy France.

3off Hugh P's 3.7m Wind T's (9 years).  .. 5kW PV on 3 Trackers, (5 yrs) .. 9kW PV AC coupled Used/SH GTI's, on my OzInverter created Grid, and back charging with AC Coupling to the OzInverter to my 48v 1300ah batteries.

george65

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Re: unusual car battery shelf life
« Reply #6 on: January 23, 2017, 06:35:12 AM »
My brother bought a new Toyota (big European 1800cc petrol saloon) in 1998, and yes the original battery is/was still on it 2016.

That is amazing. Never heard of anything like that. I'm thinking I did well at 4 years out of a battery!

Quote
Interestedly the battery is very large compared to the new types,

I hate small batterys with a passion!
My wife and daughters cars not only had the small batterys but the small skinny terminals on them too.
They soon got the flick. I got the battery leads of the older models and changed them over.  Then I got the Biggest Muther batteries I could put in there and bolted them in.

The batteries in a lot of new cars are like torch batteries. I notice though that they all have trays that accommodate MUCH larger batteries than what is specified with the things.  I have 2 batteries in my 4wd. I don't take it off road, I just feel secure with plenty of battery power. I bought an after market tray for the 2nd one and bolted in another big marine battery. Got some leads off another car and just paired them up and also doubled the earths. I have one from each battery going to both the engine block and the chassis. You can have a lot of problems if the earths are not good so I now have quadruple what the thing came with.
 I can start on either battery and the combined CCA and reserve is over the top but that's fine with me.

I once left the lights on all day and came back to the thing 9 Hours later and it fired up like any other time. I did take the long way home though to let them charge up. You could hear the poor alternator whining all the way home. I'd like to fit a 2nd alt as well.  Upsizing the one on it isn't so easy as it's a diesel and the Vac pump is on the back of the alt.

I had a couple of old diesel mercs some years ago. a couple of the oldest cars I had owned since a kid but goddam if there wasn't someone knocking on the door every week  ( or 3 different people in a day) wanting to buy the things. They weren't pristine, pretty much the opposite but there was forever some Arab bloke at the door wanting to buy the things.
When I did sell them the guy told me they would be shipped back to the middle east to be taxis.  I told him, one was rusted out and the other had been hit and was bent in the middle. Didn't perturb him one bit. He was adamant they would fix them and get them back on the road.  I kinda strongly suspected that nothing would be done to them at all and they would probably not even get registered properly.

I had taken the engine out of one as I was told it had been rebuilt when I bought the car. Didn't believe it at the time but over the years I owned it and saw how it went and the compression it had I came to believe it. As I was running them on veg oil I pulled the engine out of the rusty one to put in a boat hull I wanted to buy for cheap boating as well.
I told the guy that the engine had been taken out to get fixed but wasn't worth it so it had been thrown away.   The persistent bastard kept coming back for months after asking if I had " Found" the engine and offering money for it.

It's still up the back  and maybe this year some time I'll get round to finding a boat to put it in or couple the thing up to a decent gen head.

There are a lot of stolen cars here that are put in containers and shipped to the middle east and asia. I think they must be pretty slack or corrupt in these places and don't ask too many questions or want proof of where the car came from unlike here.

I wonder how they go with batteries in hot climates like the middle east?

Bruce S

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Re: unusual car battery shelf life
« Reply #7 on: January 23, 2017, 08:36:32 AM »
Having lived in Saudi Arabia back in the late 80s, and drove a cool "firefly" I can say the battery had two things going for it.
1.) twice the size of what it would normally by for a 1000cc 4cyl 5 spd
2.) It had a sticker that said built for high-temp weather.
Never had an issue with it starting, of course if we had , a rolling start of the clutch would've been an easy thing.
When I first got there, I was told to never hand the attendants a 20 and ask them to fill it up. Only had them a fiver and let it go.
No selection of  high-test or mid-grade, only one type, which makes sense.
Even the cassette tapes I still have somewhere, have the little label "built for high-temp weather".

Bruce S
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mab

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Re: unusual car battery shelf life
« Reply #8 on: January 23, 2017, 04:52:29 PM »
Quote
If that's true, then it must be something about the way lead acid batteries are charged and discharged that ages them, not time itself.

more or less true; If you want a battery to last a long time then keep it in the fridge, don't actually use it, and give it a periodic top up/equalisation charge. If you do want to use it, warm up to room temp first for best results.

Thinking about it, the battery in my car is still the one that was in the car when I bought it (2nd hand) in 2008 and it still starts the diesel engine fine, despite being above the engine and used more-or-less daily - although I haven't done any testing to see how far gone it might be.

I'd be disappointed if a car battery lasted less than 7-8 years from new though TBH; granted the climate here is relatively battery friendly - no extreme temperatures - but if a battery fails before 3 years I'd suspect it of being particularly poor quality, or having suffered a significant amount of abuse.

have to say I'm surprised they don't last long in Florida though -

joestue

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Re: unusual car battery shelf life
« Reply #9 on: January 24, 2017, 01:30:47 PM »
if they only last 2 or 3 years it would be worth diluting the acid as an experiment, and you may need to lower the voltage after the alternator by adding one additional diode drop after the alternator.


3 lithium ion cells could be a drop in replacement if you modify the alternator to generate a maximum of 12.5 volts.

dnix71

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Re: unusual car battery shelf life
« Reply #10 on: January 24, 2017, 08:59:37 PM »
have to say I'm surprised they don't last long in Florida though -

The temps in south Florida ruin a lot of things. Most people here avoid German cars because they can't handle the heat. The humidity and high temps year round ruin leather interiors. One of the runnng jokes here is that people will park out of the way if it means a shaded spot.

A car without a/c is almost unsafe to drive long distances in the heat of summer, and unsafe in the rain because the interior will fog up.

I parked a van in the sun one morning and came out with a digital no-touch thermometer and it was 175F on the dash. That's above the minimum needed to safely cook meat. Under the hood temps are at least that high sitting in traffic. That's why batteries here usually die after 2 years.

george65

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Re: unusual car battery shelf life
« Reply #11 on: January 25, 2017, 05:25:08 AM »

We have had 3 over 40oC days here ( and many other parts of the country in the last week.
Where my father is a little north of me, they had one day which was 46C ( 114) and another that was 44. All the rest were 40-42. A little inland of him they hit 48. Admittedly that is unusual but certainly not something which doesn't happen every year.
This is in the lower, cooler end of the country where they farm livestock. Right up north it's far worse and don't even talk about the centre. Dunno how people can live there.  40+ is an average temp.

We have a lot of humidity here too but where my father is is so Dry, the air burns when you breathe it and it's almost impossible to drink enough water.  You put it in but you never have to visit the bathroom because you sweat it all out.

You want hot, come to OZ.

Harold in CR

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Re: unusual car battery shelf life
« Reply #12 on: January 25, 2017, 08:55:03 AM »

 Slightly off topic but inline with battery results, my buddy here in Costa Rica built a small battery pack using 26650 ("D" sized nearly, A123M1 lifepo4 battery cells, and it starts his nissan van easier than the past 2 lead batteries. The size of the pack is less than half the lead batteries. Can't remember the S-P configuration, but, will report back if anyone is interested.

 These were used from Power tool packs where 1 cell always fails but the rest are fine. Lithium batteries have hardly any internal discharge unlike lead batteries.

george65

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Re: unusual car battery shelf life
« Reply #13 on: January 25, 2017, 08:03:03 PM »

I have been reading up on these DIY " Power walls " made from used laptop 18650 Cells.
People disassemble the packs, test the cells, get rid of the faulty and weal ones and build hundreds of the things into battery banks.

The thing I don't get is what is to stop the cells falling over a week after you build them into these packs?  It would seem that your bank is always going to be on a downward spiral as the cells fall over and they may well cause a drain on the rest of the bank.

It seems a relatively new idea and I can't find anything on someone that has had one a few years and showing what their fall off rate has been.
It would seem to me that if a cell or 2 has fallen over in a pack, the rest must be heading the same way given they would have been exposed to the exact same operating conditions and be just as old.

All that said, I'd like to give it a go in a test pack that was a decent size but not with too much effort involved.  A friend of mine has supposedly been talking to someone about hauling E waste in his truck from once city to another for recycling so if he got that contract I'd have a goldmine of cells I could tap into.  Other than that, I have picked up a few laptops out the back of the local office supply store as part of their ewaste disposal program.
Can't believe people throw out working computers these days that still have ALL their data on the HDD's. That would be a goldmine of another sort for the Shonky and fraudulent and one I'm sure they are already onto.

People keep saying the price of batteries is falling but that only applies to newer technologies. How far they fall is always the question.
Lead acid is an old tech and the price of those batteries hasn't fallen in years despite the ever growing demand in things like cars, forklifts and industrial backup systems just to name a few. If Lipo or anything else could ever become cheaper than lead acid or if there were other factors in Automotive markets that justified a higher price remains to be seen.
I read the Tesla factor is gearing up to produce millions of a new cell which is about 3 times the capacity of the 18650. Again, how long they take to become mainstream and the end price remains questionable.

Funny, we always look forward to new and exciting products of the future but when they are mainstream, they are ho hum and forgotten about and we are waiting with anticipation for the next miracle forgetting the ones we already have that we waited with bated breath for them to arrive. :0)

frackers

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Re: unusual car battery shelf life
« Reply #14 on: January 26, 2017, 03:52:34 AM »
A lot depends on how you test the cells.

A mate of mine has found that an ice cream container (for a local brand)  hold 64 cells - about 100 amp-hrs and he prepares them by charging to 3.9 volts, rest of a couple of hours, checks that they are still over 3.8v and then times them to 3.3v at 1C discharge (i.e. about 2 amps). If they don't meet his criteria then out they go. He tells me that he'll only be charging them to 3.8v so only 80% charge but at that you get 10x as many cycles as when going to 4.2v and 100% charge.

By testing quite thoroughly, he reduces the chance of a duff one getting through and by staying well below 4.2v when charging he avoids the area in the use curve that has the highest failure rate.

At last count he had 6 containers and is aiming for 8 so he can run them through a set of single panel grid tie inverters that produce 250w from a 60 cell panel. He'll be using them to time shift his grid tie solar system to allow for more inside the house use rather than exporting the power and not getting much for it.


Robin Down Under (Or Are You Up Over)

george65

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Re: unusual car battery shelf life
« Reply #15 on: January 26, 2017, 04:22:05 AM »
He tells me that he'll only be charging them to 3.8v so only 80% charge but at that you get 10x as many cycles as when going to 4.2v and 100% charge.

By testing quite thoroughly, he reduces the chance of a duff one getting through and by staying well below 4.2v when charging he avoids the area in the use curve that has the highest failure rate.

Thanks for that. I wasn't aware of these cells being fully charged being in fact a detriment.
Do they have a minimum voltage/ capacity that gives them better longevity?

I always thought the better charged you kept ANY battery and the less you took out of it before recharging the better. Obviously not with all types.
I would imagine the laptop manufacturers push all they can into their packs to give them the best run time as possible and longevity of said packs is a secondary concern.  More profit in selling replacement packs as well as the value of advertising the longest run times for the machine.

A nice round capacity number in the ice cream containers would be good to work with.

Maybe in time car batteries will be the same size but instead filled with 18650's instead of acid, lead and separators.

Harold in CR

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Re: unusual car battery shelf life
« Reply #16 on: January 26, 2017, 06:31:54 AM »

 george65, go to endless-sphere.com and you can find LOTS of people using used batteries. Laptop cells are not designed for things like motorcycle batteries. Find used power tool batteries. Try to find shops that work on power tools and see if you can get the throwout batteries.

 Usually, the first cell in the battery is the one that craps out. It seems that the push of charging and discharging is the cause for the first cell to handle that abuse.

 Laptop batteries would be OK for use as fracker says. It's just that it takes a bunch to make a pack and the size of the pack is too large for electric bikes and motos.

Makita packs were, for years, the go to for electric bikes and small moto-scooters. The had a spinel technology that effectively helped in self balancing.

 There are electric car batteries that can be disassembled to get smaller pouch lithium manganese cobalt cells, or use the modules, like Nissan Leaf and Chevy Volt batteries.

 I use Volt batteries in my homemade motorcycle at 74V nominal-83V directly off the charger. I have a 120V 111V nominal in my new build and will use 24V-22Vnominal and add 1 more cell group to makea 24V at 28V full charge, which I will limit to 24-25V for my home and shop conversions.

 I just purchased a 2017 year 10 mile use battery from a car salvage business for $2000.00 shipped to Florida and will ship it to my buddy here in Costa Rica for powering home built farm vehicles. These have a 10 year life as a highway car battery, so, could last well over 15 years with regular maintenance.

Bruce S

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Re: unusual car battery shelf life
« Reply #17 on: January 26, 2017, 07:15:56 AM »
For me, the HP laptops seem to be the best to find for full sets. There's a 1-wire thermal hookup in the pack that gets dislodged.
Once I open the pack and see that, I know the whole pack is good.
I still pull the pack apart, snip the connectors and start charge testing the batts, out of 7 full packs, I've only had one battery actually bad.
I'm with frackers on the charging part, rarely do I let these get up to full charge. My unofficial test is to charge them using a little 6V solar panel and one of the single LiPo charges you can buy 10 at a time for something like $5/USD with free shipping. I let these charge for a few days, take a voltage reading , let them sit for a few days , then read the voltage. Anything that has dropped even a volt get put into the solar powered LED patio light bin.

I've also been given some Dewalt battery packs, I'm not impressed with them going from real good A123 batteries to something else with lower Ah ratings, BUT free is free.

Cheers
Bruce S 
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Ungrounded Lightning Rod

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Re: unusual car battery shelf life
« Reply #18 on: January 26, 2017, 08:25:14 AM »
As I understand it, the main things that kill lead-acid cells (in normal service) are:

1) letting a cell stay less than fully charged for more than a couple days, either by the whole battery being discharged and not recharged within a day or two, or not keeping it equalized, so some cell(s) are not fully charged when the charging system decides the battery is full.
2) letting the plates become uncovered by water loss, then be damaged by exposure to air
3) letting the suphuric acid coencentration become different at different heights, due to repeated small discharge-charge cycles with nothing to mix it.
4) Discharging the the battery so deeply that some of the plate material flakes off and piles up in the bottom of the cells - eventually piling up enough to put a high (then progressively lower) resistance leakage across the bottom of the plates, discharging the cell progressively faster (and making it flake faster) until it doesn't stay charged overnight.  (One of the advantages of the Sears Die-Hard battery, at least historically, is that it had an extra-big pocket at the bottom to collect these flakes.  So it could last longer in the field before they piled up enough to start shorting and self-destructing the cells.

Other mechanisms are much less likely to occur or take a lot longer (such as expansion of the positive pole piece until it starts to crack the case - which takes a decade or more.)

1) is sulfation:  As the battery is discharged the sulphate ions from the the plates turn into lead sulfate.  At first this is amorphous and easy to turn the battery back into Lead, Lead oxide, and CONCENTRATED sulphuric acid by recharging.  But with time (like a couple days) the the lead sulfate gradually crystalizes into, first a form that MIGHT be broken up by specialized charging regimes, then into one that just isn't going to react.  The crystals not only stop participating in the reactions, lowering the battery capacity, but they also are highly resistive, tending to form a coating over the plate surfaces, and they're a different density than the other states of the plate, tending to break it up.  You can accumulate damage from sulfation in only a few days of undercharge - either overall undercharge (damaging the whole battery) or unequalized operation (damaging the particular cells that had slightly higher self-discharge and thus ended up with persistent lower charge levels).

2) (loss of water from the electrolyte) can occur due to evaporation, but occurs mainly due to overcharge  (including the deliberate slight overcharge during equalization), resulting in electrolysis of the water into hydrogen and oxygen.  This gas bubbles out of wet cells, which must be refilled with water occasionally to replace it, before the top of the plates are exposed and the cell damaged.  Catalytic caps can recombine the bulk of the gas back into water if it isn't generated too rapidly (as can reactions with other components added to the plates in sealed cell designs), greatly extending the time between refills for wet cells (or time until death by dry-out of sealed cells).

3) is stratification.  A lot of small discharge-charge cycles can cause this to build up faster than diffusion equalizes it.  The differing concentration of acid at different vertical positions results in corrosion of the upper portion of the plates and sulfation of the lower.  (You can think of it as the cell being overcharged at the top and undercharged at the bottom.)  In wet cells this can be combated by stirring the electrolyte (impractical), shaking the cells to slosh the electrolyte around (happens in vehicular applications), or mixing it using the gas bubbles from slight overcharges or equalizing charges.  (A similar effect to stratification can occur if the battery has a substantial temperature gradient between the top and the bottom.  Avoiding this is part of the theory behind battery racks that provide a gap, or insulation (such as a layer of wood) between the bottom of the batteries and a concrete floor.)

So if wet-cell batteries are floated to keep them charged or recharged soon after discharge, given regular small equalizing charges, and kept filed by regular maintenance or catalytic caps and occasional maintenance, the short-term failure mechanisms are avoided.  Early recharge and regular equalization heads off sulfation from undercharge.  Bubbling from the equalization avoids sulfation and oxidation fro stratification.  Heading off sulfation and avoiding deep discharges also avoids flaking and the resulting self-destruction.  Catalytic caps can make the cells stay wet for years, rather than months, between refills, despite gassing from the equalization/destratification charging regime.  So such cells can last a decade or more before the next big mechanism - positive terminal corrosion - takes them down.

But if they're abused, like by deep discharges, being left discharged, or allowed to become unequalized, they can be killed in a matter of weeks, or even days.

OperaHouse

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Re: unusual car battery shelf life
« Reply #19 on: January 26, 2017, 08:49:19 AM »
I've designed my camp to be almost battery less. The one battery I use is out of the vehicle I don't bring. Using a battery bank 5 months a year, even if kept at a charge the rest of the time, seems like a recipe for problems. I bought a new BLEM auto battery from a distributor a few years back, one that had set on a shelf for a year and then returned.  It was super cheap and got me out of a jam. It only lasted a year and a half.  Not sure if that was from being sulphated at the start or my hap hazard charging every couple of weeks in the winter.

I have a couple old car batteries I use in the garage for power.  These appear to have the same capacity of a SLA or 5AH. Have a feeling they suck up more AH being charged than can ever be taken out of them. OK for the garage where they run a light or radio occasionally.

My laptop just came up with a red X on the battery saying "consider replacing your battery pack." The laptop is already held together with tape and big seams still show. Now I'll have to Duck Tape the battery pack!
« Last Edit: January 26, 2017, 09:50:06 AM by OperaHouse »

george65

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Re: unusual car battery shelf life
« Reply #20 on: January 30, 2017, 07:44:21 PM »

Just read something that said the maintenance free/ sealed type batteries don't last as long as the conventional type.

Has this been the experience of people with these ultra long lasting examples?

joestue

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Re: unusual car battery shelf life
« Reply #21 on: January 30, 2017, 08:48:45 PM »
Maint free batteries might have more calcium, and they do have a higher acid concentration, in attempt to increase the recombination rate and reduce water loss. If you add water to a maintenance free battery they behave as flooded cells until the water level drops to partly saturated fiberglass. You could decrease the acid concentration. But then you might have to regularly add water

Gordy

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Re: unusual car battery shelf life
« Reply #22 on: February 27, 2017, 10:48:07 PM »
joestue, The maintenance free car batteries that I forced the tops off of, looked like flooded cells inside to me. One was in a truck when I bought it so I don't know how old it was. But I got 5 years out of it before it acted up. I forced the top off and added about 1/2 of a water bottle to each cell and put the big charger on it over night. And got another 4 years out of it, when the truck went to the scrap yard.

The best so far is the Motor-craft battery in the wife's 2002 Ford Focus she bought new, just put a new battery in it in Nov. 2016

Dad got 10 years out of one in his 81 Ford Fairmont that he bought new. I think what killed that battery was the starter went bad and was drawing 450 amps to turn over that little 4 cylinder engine.

Gordy in MN