Modern sealed batteries and Series Electrics

I have read that modern sealed batteries are not suitable for older vehicles.

These batteries are said to need variable charging voltages, which modern vehicles are designed to provide.

A Series alternator apparently does not produce enough voltage to properly charge one of these batteries, and will shorten the battery life if fitted.

An old style mains charger is also supposedly not suitable for these batteries.

Is there any truth in any of that?

My 2 1/4 Diesel Series is currently fitted with a 640CCA size 643 old type lead acid battery with removable cell caps. This battery reads on a digital test machine as being only 40% effective, and in need of replacement. It will usually start the Series after it has sat for a few weeks, apart from in very cold weather. In this case, a few hours on charge normally sorts the problem. It came with the vehicle when I bought it in 2012, so I assume it is at least ten years old. I don't want to buy a new one only to ruin it by not using the vehicle often enough.

Sounds like you have answered your question, just put on a mains charger to keep it topped up, would be the same what ever liquid lead acid battery you have. So called sealed battery's are not totally sealed they just have a more robust system to prevent electrolyte loss and can be charged with a normal mains charger.
The type that need a special charger are the sealed lead acid gel types where the electrolyte is in a semi solid form.
Worst thing for any battery is letting it go totally flat, charging from this state can be dangerous, more so if a boost charge it tried.
It is a thing with older style alternators in that they tend to not fully recharge a battery that say was down some. Trickle charge every two/ three months.

At 10 years old it’s fair to say it’s seen it’s best days , my series 3 with original alt can put out 14 volts , my 2015 golf last week wouldnt turn over one cold morning despite a slow trickle charge a few days with a smart CTEK charger
New agm stop,start from Tanya was cheap and eye opening in its starting ability , an old dying battery is something that creeps up,slowly until it lets you down. Treat yourself and the landy this Christmas and get a new battery
The last landy battery I got was a yuasa silver with 5 year guarantee

My last battery purchase was from Halfords about six years ago with ‘a lifetime guarantee’ tag on it. The receipt is starting to fade a bit and touch wood the battery is good for a while yet but it will be interesting to see the response from the counter when I take it back in.
On the posters point one of the best bits of advice I have had on here is plenty of good earths and keep them clean.

Thanks for the replies. If it was a vehicle I needed to rely on I would buy a new battery.

My series has a sealed battery on it and it starts and charges fine. Ive just started it this morning after standing idle for at least 3 months and it turned over well until the petrol pumped through and it started.

Col

I have one on an old Brit bike which are not known for sophisticated charging systems and its fine after a couple of years, holds a charge well and seems to be charged up by the bike when it gets the occasional run

Modern sealed batteries that have been out for 20 odd years!

Agreed, modern sealed batteries are fine. But avoid gel type, they cost more and in my experience fail early if not used regularly.

lynall said:

Modern sealed batteries that have been out for 20 odd years!

Click to expand...

TRUE, hard to find the older cap types today.
I repeat the one's to take special care with are the sealed gel type and any lead acid that has gone very flat. Last spring I had put an old battery used to power an electric fence on charge in my workshop when ten mins later it exploded I was only some five feet away and did not half jump when it detonated chucking bits of casing and acid all around. Good job I was facing the other way and was protected by my cold weather hat and coat. Only got some splatter on the back of the neck quickly washed off under the hose.

Feck! Was that just a build of hydrogen gases causing a big pressure inside casing
Was it an agm or the lead acid that exploded , sometimes that have screws to loosen when charging

It was an old lead acid battery that was past its sell by date for vehicle use but still produced enough volts/amps to run an electric fence unit.
Blew the whole top off 3 of the cells. What likely happened was a build up of hydrogen gas and an internal short in the battery and when the concentration was right it detonated. Second time it has happened to me although I was not there when it happened the first time some years ago, heard it though.
Just saying be careful when trying to charge old batts who's starting volts are low.

Scary I’ve got a few lead acid oldies in garage ,I’ll be more careful from now on

Use a Modern battery on my early ninety. I don’t use it very often, just pop it in charge every now and again.