LIfe expectancy for a Powersafe SBS40 (38Ah) battery

[heptagon]

Usual story, 7 left in garage (K series 1.8), used infrequently, put on an Optimate motorcycle charger when I remember or it's flat.  The battery is 7 years old and I've always disconnected the battery master switch when in the garage for the 5 years I've had the car.

The other day it wouldn't crank the engine, I put it on the Optimate, charged it, Optmate lights went green but it still wouldn't go.  Bump started, drove 20 miles, came home, tried to restart and it refused again.

I've now removed the battery for a long charge, would I be better putting it on a more powerful charger.  The Optimate only delivers 0.1 amps so is very slow but has worked ok in the past. I have a Halfords car charger.  Voltage on the battery seems to be 11/12 volts across the terminals at present, haven't tried a cranking test yet.

I also understand from reading up that the SBS40 is a powerful battery so I'm surprised it's died this quickly.  I also checked the prices and if I replace it need something cheaper! It's currently fitted on it's side with a bespoke bracket, so something a similar size would be the easiest replacement (250x95x190mm).  Can anyone recommend something a bit easier on the wallet?

Thanks :-)

 

 

 

[Jonathan Kay]

Voltage on the battery seems to be 11/12 volts across the terminals at present, haven't tried a cranking test yet.

That's not encouraging. But is that on a multimeter or does the charger have some sort of indicator?

Does it need topping up?

Still worth checking all relevant feeds and earths: disconnect, clean and reconnect.

You've given it some time on the alternator, but it may still be worth a couple of hours on the unconditional charger.

IMHO the most sensible battery for most 7s for most purposes may well be the PVR "Clubman" 22. (I use a PVR 25.)

Jonathan

 

[heptagon]

Measurement was on a multimeter, I'll see if I can check the levels and clean the contacts as well.  If it's no better after a good charge I may have to say goodbye to it.

[heptagon]

Thanks for the help Jonathan, I've ordered a new PVR25 now, Sean

[Roger Ford]

7 years is pretty good, especially if it's gone flat a number of times.

[Alan Reeves]

Please clarify for me:

The old battery is 38ah ( and i really have no idea what that means in everyday terms)

the PVR25 is just 20ah

my assumption is that the more Ah the better ? 

there was an article on this a few years ago but I cannot locate it.

 

 

[Jonathan Kay]

That Amp x Hour rating describes how much energy is stored. For well-starting 7s it's not very important. (It would be if you had to attempt to start the same 7 many times in a row or lots of different 7s!)

The other widely-used ratings "Cranking currents" of various flavours are more relevant, but if the 7 is starting correctly then all sensible batteries will be fine.

The problems come if you are trying to start a badly-starting 7 multiple times with no other source of power. 

The PVR 25 will be fine.

Wikipedia description of battery terms and ratings.

Jonathan

 

[Alan Reeves]

Thanks will look at that