Sad story - freezing batteries

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Nick F

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Callisto
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1974 Grand Banks 42 Classic, Hull 433
I was given a set of 8 very nice looking golf cart batteries in September by a dock neighbour who is going lithium.

I sat them on the dock next to my boat and expected to add some of them to my house battery in the spring.

I just found that they are at about 2.5 volts and the cases are slightly "bulging". One case is actually split on top.

We had a cold snap in January (cold for Vancouver!) and the temperature went to -14C (about 7F), so presumably this was the problem.

I had no idea that lead acid batteries could freeze. Apparently they can freeze at around this temperature if fully discharged.

Has anyone else suffered this problem? Is there any hope for recovery?
 
Sorry but they sound good as core returns. The acid will still burn the heck out of you so be cautious.
 
They're scrap. Once they've frozen it's likely that they've suffered serious internal damage and will never be usable again. Plus, they're likely significantly sulfated from sitting partially discharged, so they're not likely to be in great shape even if they didn't suffer any structural damage from freezing.

Lead acid batteries can definitely freeze. The more charged they are, the lower the freezing temperature gets.
 
Interesting. I’ve lived and worked in places where overnight temps got to -40. I never had a freezing issue when battery acid around 30 degree baume. Maybe the previous owner ruined them prior to donating to you by diluting below 25 baume or so with distilled water because he cooked the batteries. If the solution is below a sg of 1.2 or so you found the reason.

Maybe he needed a disposal avenue?
 
We routinely have weeks of 0 to 25 below (F) every winter here and my FLA batteries do okay. Our marina disconnects batteries during winter layup, and they're certainly not dead or mostly discharged when disconnected, but on the other hand the charge certainly declines sitting idle from October/Nov to April. My batteries usually last 3-4 years. Wonder what happened to those.
 
If the batteries were left on the dock in a state of discharge then yes they can freeze at -14C. I saw temperatures at -37C in Kamloops back in January so it’s very possible that they saw temperatures of less than -14C.

Had the batteries been fully charged they would most likely not have frozen.
 
Whether it freezes or not, you can't leave flooded batteries lying about for several months without charging them. They will be no good, even if kept at a nice 70 degrees. The self discharge rate of flooded batteries, especially older ones, is significant, a few months and they will be dead and sulfated.
 
Pretty common actually for some batteries stored in cold area and not on trickle charger...

https://petesgolfcarts.com/battery-... shelf life is,15% per month at 77º F (25º C).

The limiting factor of battery’s shelf life is the rate of self-discharge which itself is temperature dependent. VRLA batteries will self-discharge less than 3% per month at 77º F (25º C). Flooded batteries will self-discharge up to 15% per month at 77º F (25º C).
(my comment - most are not near the 15%....probably less than 10% if stored in cool, dry place)

https://homebatterybank.com/do-car-batteries-freeze/#SnippetTab
 

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Actually cold temps are your friend if storing a fully charged batty w/o maintenance charge available as the self discharge rate goes down w colder temps.
But as clearly outlined above having / keeping them at full charge is key.
Agree their usefulness is for trade- in core value or for sale at a scrap yard for lead recovery.
 
Actually cold temps are your friend if storing a fully charged batty w/o maintenance charge available as the self discharge rate goes down w colder temps.
But as clearly outlined above having / keeping them at full charge is key.
Agree their usefulness is for trade- in core value or for sale at a scrap yard for lead recovery.

Sulfation happens more slowly in the cold as well. The ideal storage condition for lead acid is pretty much fully charged and reasonably cold.
 
Three different boats dry stored for 5-6 months at Lake Powell with no charger. They had standard sealed 12v batteries and were fully charged at layup. Never ever had a problem even when restarting.

Yes batteries lose power over time and are best kept on a charger. But in this case I’d guess the free old batteries were replaced and given away for reason.
 
In the seventies French navigator wintered in Antartica, during this time they let the boat alone without hâter during week, and the batteries never frozen.
Book name " Le grand hiver" by Poncet and his wife
 
For the millions of us who live in states (or provinces) with severe winters, including here ag country where all forms of farm machinery sit dormant over the winter with only a small fraction on trickle chargers, this discussion abut frozen batteries is amusing.
 
(my comment - most are not near the 15%....probably less than 10% if stored in cool, dry place)
These were used, and possibly well used batteries. the self discharge rate rises as the battery ages, 30%/month would not be uncommon for flooded later in life.
 
These were used, and possibly well used batteries. the self discharge rate rises as the battery ages, 30%/month would not be uncommon for flooded later in life.

You should have been more specific in your last post.

30% per month should have signaled one replacing them a long time ago.

Many references I read say 3% for new/healthy sealed batteries and around 5% for flooded.

No need to believe me...others can research enough and see what I have found....as well as some of the anecdotal info some have posted here.
 
You should have been more specific in your last post.

30% per month should have signaled one replacing them a long time ago.

Many references I read say 3% for new/healthy sealed batteries and around 5% for flooded.

No need to believe me...others can research enough and see what I have found....as well as some of the anecdotal info some have posted here.

They were replaced - that's why they were discarded and sitting on the dock. You should read the posts more carefully.
 
Fwiw, 2 -10 plus year old Optima blue top batteries in my center console here in NJ last charged in October’23. Just checked the voltage and both are reading 12.61 volts! I was told the temperature was below zero F several times. I know what their eventual replacements will be.
 
Whether it freezes or not, you can't leave flooded batteries lying about for several months without charging them. They will be no good, even if kept at a nice 70 degrees. The self discharge rate of flooded batteries, especially older ones, is significant, a few months and they will be dead and sulfated.

Not sure I need reading training.

Just pointing out which is flat out incorrect. Older (really...not very specific) sure, but new and newer don't discharge that quick. If they were in that poor of condition when you were leaving them for months and depended on them for any reason, well batteries need some understanding for proper use.

So even batteries several years old if properly maintained and checked before extended storage should certainly go for months in freezing (not Arctic) conditions without damage. That is because their discharge rate is usually less than 10%.
 
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Sorry but they sound good as core returns. The acid will still burn the heck out of you so be cautious.

News Flash
You can't just leave a flooded Lead acid (FLA) battery to its own devices, they need to be charged up periodically, maybe topped off every 2 weeks. They are subject to self discharge.
Thanks for sharing so others may learn this lesson
 
News Flash
You can't just leave a flooded Lead acid (FLA) battery to its own devices, they need to be charged up periodically, maybe topped off every 2 weeks. They are subject to self discharge.
Thanks for sharing so others may learn this lesson

True.... a smart trickle charger whether a plug in or solar is best for standard FLA batteries...but realistically millions leave FLA batteries in their small boats/RVs for much more than 2 weeks and life goes on.

If freezing temps are expected, heightened awareness of their state of charge is warranted.

Large expensive house banks are costly to replace so it is so very true spending a few bucks to ensure their health with trickle charging is advisable.
 
The moral of the story, for a variety of reasons, is keep the batteries charged.
 
Greetings,
I've heard that if you are storing batteries ashore, do NOT place them directly on a concrete floor. A piece of wood underneath will suffice.
 
Greetings,
I've heard that if you are storing batteries ashore, do NOT place them directly on a concrete floor. A piece of wood underneath will suffice.

From what I know, that's an old legend from when battery cases were slightly permeable many years ago. No such concern with modern plastic battery cases. You're more likely to get extra self discharge from conductive dirt on top of the battery contacting the terminals.
 
From what I know, that's an old legend from when battery cases were slightly permeable many years ago. No such concern with modern plastic battery cases. You're more likely to get extra self discharge from conductive dirt on top of the battery contacting the terminals.
The concrete floor thing was old technology, no need to to worry today. The dirt thing on top has validity. My understanding is that a LA batt left along will discharge about 3% per month.
 

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