Extending the life of batteries

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njthake

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Prolonging the life of lead/acid wet batteries (my batteries) has become an obsession. I buy good quality deep cycle batteries (Trojan then Rolls, now Trojan) and good quality (Victron) charger and set up the best I can for winter storage-Float charge with marina supply.
There is the weak link, marina supply! Especially in Greece. Whenever possible I ask friends to check my supply is ok and more often than not it’s tripped off, heavy rain usually the culprit.
Unrectified this leaves the best batteries helpless and after a month or two they lose their charge below the threshold where self damage starts. I have no solar panels.
In the old days ( I’m a bit long in the tooth) batteries were always supplied “dry” with no acid. The retailer added the acid when the battery was sold. I am not sure if that is still the case. The point here is that with no acid there was no sulphation/deterioration and the shelf life was infinite.
Question for the experts.
If I remove the acid from the batteries over the winter period can I relax in thinking that they will not deteriorate. I understand all the problems involved in removal, and that the cells and lead (which has become a sponge) may need a flush with distilled water to become clean, but is there any value in the program. The price of replacements makes me look long and hard at any alternatives.
 
I isolate my Trojan batteries so there's no drain except self discharge and then compensate for this by using a 30watt PV panel to slow the rate of discharge. The panel is only used when I'm not on board and for the cost of batts £100s or £1000s I would consider it £50 well spent!
Dave
 
Sounds like a difficult process to ensure you have it done correctly.

Surely easier and more effective to wire in a smallish panel via a controller that will just maintain them at the correct voltage. If the controller has plenty of spare capacity then you can add a couple more fixed panels for arranging when at anchor.
 
I agree - why would you not add a panel. Its easy and pretty inexpensive.

I have rather more than necessary with 1,000 watts, but even in the UK winter I can be independent of any other power source.
 
No if you empty the battery you will destroy it very quickly. Batteries supplied dry are built either with unformed plates, or with plates which have been formed and then washed and oven dried. You cannot do it with an assembled battery that has been filled. Shelf life of a battery supplied dry is typically 12 months, not infinite.

If you completely isolate your batteries when leaving them, making sure they are fully charged first, then most batteries will last 6 months without damage provided they have a good recharge before using again. However if you have T105s or some other deep cycle batteries, the self discharge rate is higher particularly towards end of life, 3 months would be about the safe limit for those.
 
njthake said:
In the old days ( I’m a bit long in the tooth) batteries were always supplied “dry” with no acid. The retailer added the acid when the battery was sold. I am not sure if that is still the case. The point here is that with no acid there was no sulphation/deterioration and the shelf life was infinite.
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I well remember the large carboy of acid we had in a corner of the service bay. When I was looking for batteries to Portugal, I asked Tayna about having them sent dry so an ordinary carrier would handle them. Reply was that unfilled batteries would be more expensive because it would be a special order as the standard production lines always fill them.
 
GrahamM376 said:
I well remember the large carboy of acid we had in a corner of the service bay. When I was looking for batteries to Portugal, I asked Tayna about having them sent dry so an ordinary carrier would handle them. Reply was that unfilled batteries would be more expensive because it would be a special order as the standard production lines always fill them.
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From a manufacturer's point of view the biggest problem with dry shipped is warranty claims resulting from inadequate commissioning procedures. It's not just a matter of pour the acid in and off you go, but that's what local distributors tend to do! As most filled batteries now has a shelf life of 6 months or more, dry ship has less to offer.
 
Two years ago I had to bring my solar panel regulator home from Greece for repair. I was advised that if I charged the batteries right up, disconnected them from everything and each other, they would be OK for the six months that I would be away. This proved to be true, all displaying voltages of 12.5 - 12.6 on my return. I still have the same batteries, performing well.
 
vyv_cox said:
Two years ago I had to bring my solar panel regulator home from Greece for repair. I was advised that if I charged the batteries right up, disconnected them from everything and each other, they would be OK for the six months that I would be away. This proved to be true, all displaying voltages of 12.5 - 12.6 on my return. I still have the same batteries, performing well.
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I think that I read recently that Trojan batteries have a higher self-discharge rate than regular lead-acid. My two Elecsol leisure batteries get a 24 hour charge in December and another in April, taking less than 1 kWh from the mains each time. Can't convert that into ah into the batteries as I don't know the efficiency of the Sterling charger but my guess is that they lose around 3 to 4 percent of charge per month.
 
vyv_cox said:
Two years ago I had to bring my solar panel regulator home from Greece for repair. I was advised that if I charged the batteries right up, disconnected them from everything and each other, they would be OK for the six months that I would be away. This proved to be true, all displaying voltages of 12.5 - 12.6 on my return. I still have the same batteries, performing well.
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Agree, self discharge doesn't seem to be a problem in practice with decent batteries . I disconnect the car battery when away for 6-7 months and it never fails to start when reconnected, with no noticeable difference in cranking speed.
 
A normal lead calcium or low antimony automotive style battery will lose something like 1% per week. This shouldn't change much through its lifetime.
Something with a higher antimony content (which is good for cycle life) like a T105 will lose something like 2% a week when new worsening to maybe 4% when nearing end of life.
 
My 1st full-time employer was Lucas, I spent 6 weeks in their battery factory, Formans Rd, Birmingham. Long since closed. IIRC, most batteries were dry charged, the lead grid plates were filled with paste and dried in a kiln.
It was not unknown for a stacker truck carrying the dried plates to the assembly line to hit some obstacle and deposit its load on the floor, The plates would lose varying amounts of paste, but they were usually still used for assembly notwithstanding.
Bad luck for the unsuspecting purchaser, I've always been a bit cynical about battery quality claims ever since.
 
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