Car battery?

Well three things cover battery performance or four if you take in cold weather performance.

Cold Cranking Amps, capacity and longevity

In this case its a straight fight between CCA and capacity.

If your car is rated to not need more than 640 CCA there is no reason not to buy the cheapest.

IME if a battery goes flat, its because

- the battery is f***ed

- there is parasitic drain

- the alternator is f***ed

- there is a n engine problem requiring extensive cranking

None of these will be addressed by a bigger battery,

My V40 is 26 years old. When the original battery eventually died I fitted a replacement with the same spec as the original. This died after 3 or 4 years. I then chose a physically larger battery that would still fit in the car. This was a Varta Silver rated at

John

At least, watch the casing size of the battery.

The hole where the battery is located, is of finite size, and the battery is supposed to stay within the footprint of the tray.

Never wear jewelry when working on a car. My friend in uni, was working on his Mini, and did not remove watch, ring, gold chains etc. His watch managed to touch (and weld) to one of the battery terminals, and when he came to class the next day, there was a pattern burned into his wrist, that looked exactly like a metal watch band :-) This is why we remove jewelry.

When you get the new battery, it comes with two plastic caps. KEEP THE CAPS. There is always a usage for those, to keep you safe. Even if you only manage to cover one of the terminals with a plastic cap, that is better than no protection at all.

At a store, automotive batteries can ship "dry". They add a fluid to the screw caps on top, and the battery is then given to you in the "charged" state. The benefit of this new scheme, is the battery does not need to sit on a charger at the store, before you take it home. Obviously, the sealed batteries that are available, those cannot come dry-charged. There would be some other ceremony for those.

When a battery finishes charging, it is at an elevated voltage. This does not hurt the car, because the electronics in the car are rated for (at least) 18 volts. If you allow 24 hours to pass, the electrodes on the battery might register around 12.6V (at room temperature). The battery voltage is quite temperature sensitive, which is why state-of-charge is so hard to do with a multimeter or with a hygrometer. Even a hygrometer reading, you need the temperature chart to correct for temperature when doing a density measurement. It is quite easy for guys like me, to be "off by 50%" on the charge state. I could for example, erroneously tell you it was half-full, when in fact it was full.

Some chargers measure the air temperature and compensate for that while they do their job. The one I bought, does not have temperature correction. This can lead to errors while charging (half-full...). When the charger costs around a thousand, there is a two wire cable with a sensor on the end, and the sensor is touched to one of the lead electrodes, to get the temperature of the battery from the lead. If a battery has been sitting at ambient long enough, then sensing the local air temperature is "good enough".

Paul

It doesn't have to cost "around a thousand" for a charger to have a temperature sensing lead. My German made Votronic charger for charging my boat betteries from solar panels has an (optional but not expensive) temperature sensor to fix on the top of one of the battery terminals. The 420 watt charger cost about £200 and the temperature sensor was £16.

It has been working very successfully for about ten years now.

Many cars made in the last decade or so have a current and temperature sensor embedded in the negative battery terminal so that they can charge at the correct voltage and try to keep track of the state of charge. John

GB snipped-for-privacy@microsoft.invalid wrote in news:vdjrog$39t3r$1@dont- email.me:

Try popping your reg into

Beware the online checkers (Halfords one, and when I compared later, all others) gave a physically too large battery for my car ...

Beware they're somewhat shady on pricing: the massive (25-40%) 'discount codes' often reduce the price to what it would be before they artificially jacked it up. You can see this from their online outlet:

ECP is used by the trade because they do same day deliveries out of branches, but the discount code shenanigans is effectively a way to fleece trade buyers because they're paying on invoice and don't play those games so have to pay the jacked up prices.

You *can* get a good deal, but you should be aware of their games.

Also to be aware that they are both very reg-focused: they ask for your vehicle registration number and it brings up a list of parts. It can be quite hard to get them to sell generic parts that aren't linked with your reg, eg if you walk in and say 'I want something a bit like this', eg 'I want an air filter that's X by Y mm' they're completely lost. Particularly a problem if your car is unusual or non standard in some way, as then the reg finds zero parts and they haven't a clue what to do next.

Theo

Theo <theom+ snipped-for-privacy@chiark.greenend.org.uk> wrote in news:c+f* snipped-for-privacy@news.chiark.greenend.org.uk:

Good tip and bookmarked.

Noted.

I'm Scotlandshire based so not for me but have decent searchdar so I usually find good deals.

Yes, I've almost been caught with that with oil filters but had the nouse to check dims, p'haps not for GB but felt Amazon might not be the place to be looking for batts.

Come to think of it I've had variable service there too, there are 2 branches in my city, neither of which I would visit but 1 in a nearby town has impeccable and helpful service.

Andy Burns snipped-for-privacy@andyburns.uk wrote in news: snipped-for-privacy@mid.individual.net:

Fair point, as posted elsewhere in thread I have had similar issues on oil filters, it pays to check.

Thanks v much for these suggestions. I checked their prices, and Amazon seems to be pretty competitive for the Yuasa batteries they sell themselves.

For example, the Yuasa 3096 is £71 at Amazon, but £94 at GSF.

Similarly, the 5110 is £91 at Amazon, but £112 at GSF.

The other batteries in the OP were from Amazon Marketplace sellers, and and those seem to be priced similarly to elsewhere.

First thing to check is you don’t need one which is ‘programmed’ to the car. Unlikely in a car 18 years old and I think it is mainly some of the German cars.

Assuming it isn’t, look for a supplier. If it does, you probably need a dealer.

I recently used GSF - a motor factors which seen to have branches all over.

You put in your vehicle details and it lists a few. There site was the only one which even seemed to find a battery for my motorhome, which is based on a very common vehicle.

Then you get to pick.

Personally, high capacity and CCA plus warranty are what I look for. A Yuasa in my case - I forget the exact number, with a 5 year warranty.

They were cheaper than others I could find and, while I collected mine as they are close, will deliver for free.

The GSF is short for their full name German,Swedish, French car parts so a good choice for Volvo although I have found them quite good for other marques as well.

GH