Battery

[les]

I’ve now raised my van off the wheels for the winter months and removed the battery, which I have charged to full capacity, my question to the electrical guys is, is it best to alternate between charging and discharging by putting a bulb across the terminals ?
Or simply charging every month or so ?

[King Kenny]

I think batteries are much better built these days. I had a battery in my garage for several years with no detriment. I would not have thought that 6 months would ruin a healthy battery. Unless someone knows better.

[ndevans]

I would just top it up every 6 weeks. It'll be fine

[geoberni]

If you have a multimeter, take the terminal voltage reading now and then check if every month. If the battery is any good, the loss should be nominal.
Fresh off the charger, you might have got a reading of 13.8v or so; but batteries need to stand and settle down.
After half a day, I would expect a reading around 12.7v or so (i.e., +/- 0.1)

Check it monthly and with a healthy battery 'on the shelf' the terminal voltage should drop by no more than about 0.1/0.2V a month.

If it drops below 12.4,V, put it on the charger.

[les]

Thanks to all for the informative answers, I shall note those voltage figures and act accordingly.

[Bill_qaz]

Have you thought of using a optimiser/ charger they cycle to maintain the battery. I've used them for year on motorcycles.
My minor is plugged into a halfords branded one whenever its not in use. The lead is permanently attached to the battery and has a sealing plug when not in use. Just plug in when not using the car and it doesn't matter for how long. I do turn off the isolator so only battery is powered. Don't forget to unplug before driving away
ask me how I know

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This is what I use on bikes

[svenedin]

I use something similar to Bill. We talked about this before. My car doesn't sit unused for very long. It does get used in winter but not if there is salt on the roads. I like to pick my guests up on Christmas Day in the Morris and it is a tradition that Morris helps to collect the Christmas turkey from the butcher. My charger is a C-TEK MXS 5.0. High quality ultra reliable. I use it on the Morris and modern car.

Stephen

[les]

Yes I do use a similar product with success, full charge shown by green light. However I usually disconnect at that point, especially as the battery is now indoors. I have this thing about leaving stuff on when no one is there. Thanks for all the advice/opinions, they are always welcome

[Bill_qaz]

Les, you need to leave it connected, when it reaches full charge in goes into a maintain cycle. They have in-line fuse to battery and fuse in 240v plug. If you have a good brand they are safe.
If you are worried then switch off at mains when not there and back on when you come home rather than off when green.
Or put rcd between plug and socket as extra precaution.
I bet many electrical items at home are powered when you are out, even if on standby, central heating, internet etc.

[les]

Yes, I take your point Bill, I guess the maintain cycle is the idea of that type of charger and I have thought of things on standby.
I’ll get an RCD. Thanks.

[svenedin]

Yes the maintenance cycle is good. Lead-acid batteries are not like lithium-ion batteries. In use in the car, the battery is always getting topped up by the dynamo when the voltage drops. Car batteries do not like discharging and sitting in a discharged state unit recharged again.

Stephen

[moggiethouable]

I must just be lazy, I have a discarnect fitted, I take it out in winter and if the battery is flat in spring, give it a charge.

[Bill_qaz]

Yes, I take your point Bill, I guess the maintain cycle is the idea of that type of charger and I have thought of things on standby.
I’ll get an RCD. Thanks.

This is the one I use on moggy, hung on mirror, then plug in and leave. Its tells you the battery voltage, when it's charging and when full. It will sit plugged in now until spring

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[geoberni]

I must just be lazy, I have a discarnect fitted, I take it out in winter and if the battery is flat in spring, give it a charge.

I'm sure mine would probably last a few months, if it wasn't for the Tracker I have fitted being a constant small drain on the battery.

[StillGotMy1stCar]

This is the one I use on moggy, hung on mirror, then plug in and leave. Its tells you the battery voltage, when it's charging and when full. It will sit plugged in now until spring
20251009_145420.jpg

Bill, I like your attention to detail, great parking, both visible wheels with the hubcap M motif perfectly aligned. What’s the other side like.

Regards John

[les]

Yes that takes some doing ! I have to remove my hubcaps and reposition them for alignment when I park !

[Bill_qaz]

This is the one I use on moggy, hung on mirror, then plug in and leave. Its tells you the battery voltage, when it's charging and when full. It will sit plugged in now until spring
20251009_145420.jpg

Bill, I like your attention to detail, great parking, both visible wheels with the hubcap M motif perfectly aligned. What’s the other side like.

Regards John

I just bought 4 wheels painted to match the car and came with M painted hub caps. My others are white wheels with embelishers So when I fitted them I aligned all 4 M so the pic was just after fitting Car is rolled back on right side pic.

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[ndevans]

My battery has been unused since being disconnected in late Sept. I've just given it a couple of hours on the trickle charger. It was virtually fully charged anyway, and only charged for 15 min or so.

[mike1864]

If it's in a car fitted with a station memory radio, or an alarm system, I suspect it'll discharge twice as fast as on the shelf; perhaps at 20mA, versus 10mA of internal self-discharge alone.
But either way, I'm with the once-a-month for less-than-an-hour brigade. This should stop it ever dropping below 80-90% charged.
Personally I'd avoid it putting it on a permanent "float" charge, smart or otherwise. There's a lot of energy in a battery, and if it - or the charger - develops a catastrophic internal fault, I'd rather the battery were fully isolated from cables potentially delivering yet more energy.