chrishelen
N/A
One of my leisure batteries is reading 13.5v even after leaving it off the boat for a week. Its over 5 years old. Is it time for the skip?
Batteries
- Thread starter chrishelen
- Start date
[70521]
Well-Known Member
What is it normally?
chrishelen
N/A
I don't know, I very rarely check them, it was only in the first of the cold weather when the boat struggled to start I dusted the multi meter off.
seumask
Well-Known Member
I'd say if you have a normal lead acid deep cycle battery its absolutely fine.
Suggest you google charge state by temperature for 12v batteries
e.g.
https://littleguy.vanillacommunitie.../battery-state-of-charge-by-temperature-chart
Suggest you google charge state by temperature for 12v batteries
e.g.
https://littleguy.vanillacommunitie.../battery-state-of-charge-by-temperature-chart
macd
Well-Known Member
...and clearly got a surprise.
13.5, as you seem aware, is very high for a (very) rested voltage. If you're moored in the tropics, it might be less extreme, but I suspect you're not. More likely somewhere the temp is going to reduce normal readings? The battery, I presume, is at home. Are you able to put a known load on it (car headlamp or similar), and see how it responds after a couple of hours?
Are you sure you read the post correctly? The reading was thirteen point five (always assuming Chris read his meter correctly).
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[70521]
Well-Known Member
Gulp...
RichardS
N/A
Provided that your voltage reading is fairly close to correct, then your battery must be fine. I'm not aware of any deleterious condition which would case an increased voltage in a lead/acid cell.
Richard
GHA
Well-Known Member
Maybe check the battery in the multimeter first?
What sort of battery? 13.5v sounds fine, if it was on charge a few minutes before......
chrishelen
N/A
Thanks for all the helpful responses. The battery at the moment is on a pontoon, next to the boat, in not so sunny Wales. I assumed it was this battery playing up as its the oldest on the boat, its a motor boat BTW. When I checked it earlier, it read 13.3 volts, and it's been off the boat for a week.
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xyachtdave
Well-Known Member
24 volt battery....?
Graham376
Well-Known Member
I suspect you need to check your meter, as GHA says. 13.3 is very high for a 7 day rested battery.
chrishelen
N/A
The meter is fine. My other batts are all 12.7 at rest and 14.3 at start of charge. But thanks for the suggestion.
Mistroma
Well-Known Member
I also thought the meter was the next thing to check after confirming it wasn't a 24V battery. Might well be worth checking that the battery inside the multimeter is OK. Of course that requires an accurate multi-meter and you might as well use it to check the boat battery at the same time.
chrishelen
N/A
12v 110ah.
oldmanofthehills
Well-Known Member
Most batteries get charged at about 14v on the boat but of necessity have lower voltage when off charge (charging must be from higher voltage source to lower voltage battery or no current will flow). Mine eventually drop to 12.5 when not connected to charger so 13.5 seems very good and what I might expect just after engine stops. Most devices on your boat except your Eberspaker heater will work fine down to much lower voltages, though chart plotters are greedy.
The real significant factor is starting current capability or amp-hour capacity. If your battery wont start the engine or lights etc go dim quickly when engine not running then its time to change it.
The real significant factor is starting current capability or amp-hour capacity. If your battery wont start the engine or lights etc go dim quickly when engine not running then its time to change it.
GHA
Well-Known Member
Certainly sounds intriguing!
chrishelen
N/A
Out of interest, how long does a good quality battery last? My boat is used most days so they get plenty of charge and discharge.
moomba
N/A
I had my Perkins 4236 fully serviced , as new boat to me in the Spring ,and she did not turn over the engineer looked at the batteries and all read 13 volts (etc) then opened them up and took fluid form each cell in the battery and put it into an eye glass/ small microscope and let me look through it.
He explained and I Seen for myself through the indicators that one of the cells in the battery was gone, but the other cell was still taking a charge and this can show on a multi meter as a charged battery , but there was not enough juice to turn over my engine,
This was one cell in 2 batteries 24v and the engine didn't even turn over. One battery changed over and turned first time.
He explained and I Seen for myself through the indicators that one of the cells in the battery was gone, but the other cell was still taking a charge and this can show on a multi meter as a charged battery , but there was not enough juice to turn over my engine,
This was one cell in 2 batteries 24v and the engine didn't even turn over. One battery changed over and turned first time.
macd
Well-Known Member
Precisely. But not for a (presumably) fairly cold battery that last received charge a week earlier. Unfortunately the OP can't tell us whether that's aberrant, but I strongly suspect it is.
chrishelen
N/A
I guess I need to get a hydrometer, but I'm not sure I can get into this battery as I think it's fully sealed.