The battery

Delmonte

Member
Messages
878
I know that the battery has a reputation for being ****... However. I last drove the car on 30th Dec. It was a 250 mile journey. Car has been in the garage until today, when I try and start it, and its flat. Surely they arent meant to be that bad, and its new battery time?
While on the subject... A friend recently bought a new battery for his car, a V8 Holden, from somewhere weird, a place that specialises in caravan batteries (!????!) But he swears by it, saying its way better and has better cranking power, turns over the engine a lot quicker on startup.
Any dangers if I buy such a battery? All i really want is one with maximum life before it goes flat while car unused?
 

zagatoes30

Member
Messages
20,759
Caravan batteries have different load requirements, tend to deliver power slower but over a longer period, not normally optimised for starting requirements however with more and more caravans having motor movers fitted there is more need for high capacity output for short periods so things may have changed.
 

Paulg390

Junior Member
Messages
80
Would definitely suggest it’s new battery time as mine can survive 3 weeks and crank strongly even at this time of year. I would be cautious about a “leisure” battery for all the reason zagatoes mentions.
 

Zep

Moderator
Messages
9,110
It might well be your battery depending on age, but you might also have a spurious drain somewhere around the car. Has it got progressively worse or suddenly decided to go flat? If the battery is old, change it and see how you go, if it is newer (say less than 2 years) then it might be worth further investigation.

Regarding battery types, Zag has the right of it. Leisure batteries are better at deep cycling (going to a lower final voltage before charging) than car batteries. But they still have a CCA rating so use that as your guide. They aren’t ‘better’ for cars, as generally car batteries are kept topped up by the charging system or a trickle charger when not in use.
 

RobinL

Member
Messages
456
I found the Tracker (which I don't use) was doing a great job of draining my battery. What everyone else says otherwise about batteries.
Pricier batteries are generally better constructed internally so will tolerate a few deep discharges better. Newer AGM batteries are recommended.

Sent from my ONEPLUS A5010 using Tapatalk
 

steve1faith

Junior Member
Messages
102
I just had a new battery aswell seems to be that time of year , my symptoms started a few weeks back with parking brake failure warning showing on start up but 150 quid battery later and problem solved
 

CatmanV2

Member
Messages
48,546
Better cold weather performance how? Curious about this one

Faster charging is hardly relevant in most cars nor is turning upside down (I hope) :D

C
 

Zep

Moderator
Messages
9,110
AGM batteries are used for stop / start equiped cars, because in this environment the increased charge / discharge functions have some benefit as S/S cars have bigger alternators to recharge the system after a trip through a set of traffic lights. I would contend that this is not an advantage for most of our cars.

The ‘standard’ lead acid batteries we buy for our cars are actually VRLA batteries. This stands for Valve Regulated Lead Acid. In practice this means that there is a valve to allow the hydrogen created during charging to escape but, crucially, there is no route for the acid to escape when turned upside down.

When they say better low temperature performance what they mean is really cold weather performance. A few extra amps at -5C is largely irrelevant when the original has been suitably sized. But in The Day After Tomorrow weather they will stay liquid longer and work better.

All batteries degrade over time, unless you keep them at around 21C for their whole life and never discharge them below the minimum final voltage they will fail sooner than the expected life span, and plenty of people fail to do this even when they keep their batteries in a specific room.
 
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Delmonte

Member
Messages
878
You didn’t lock the car?
You might be onto something here - I might not have locked it. Car is in a locked garage, and I’m not strict about locking it, it might have been unlocked. Would this cause a drain?

Also: I charged the battery on a trickle charger this afternoon, and it only took 3 hours before the charger said it was charged and maintaining. This seemed too fast?
 

Zep

Moderator
Messages
9,110
You might be onto something here - I might not have locked it. Car is in a locked garage, and I’m not strict about locking it, it might have been unlocked. Would this cause a drain?

Also: I charged the battery on a trickle charger this afternoon, and it only took 3 hours before the charger said it was charged and maintaining. This seemed too fast?

I don’t always lock my GTS in the garage, so it probably won’t be that, but worth a try.

Regarding the charge rate, it really depends how deep it was discharged, what the current from your charger is and if your charger is particularly clever. If your charger can do 8 amps the battery should reach a high state of charge (80% ish) in 3 hours but then the a finishing charge applied for another 6 hours or so at lower current and a maximum of 14.4 volts, this is the bit where we don’t know how smart your charger is.
 

MRichards

Member
Messages
278
Most modern cars seem to have parasitic battery drain so always maintain the battery voltage with a good charger when not in use.
Many so-called maintenance-free batteries lose water over time which means the electrolyte in the cells gets quite low & the battery stops operating. You can usually get access to the cells and top up with water to the correct level. A brief charge & the battery will be back as good as new.

Be aware that leaving a battery with low charge will irrevocably damage it.

I find most batteries fail through lack of maintenance and I get at least ten years use from them.
 

Zep

Moderator
Messages
9,110
There are lots of things that will damage a battery. Sealed VLRA batteries are pretty much the only ones you can buy these days, for various environmental reasons, so topping up is generally not an option. They generally only lose electrolyte if they are overcharged (for example being attached to a trickle charger continuously).

Any battery discharged below the minimum final voltage will be damaged (be life reduced) and the longer it’s left the more damage is done.

Even if you have a battery conditioner it is not a brilliant idea to leave it on charge all of the time, they need cycles to keep them match fit.
 

Zep

Moderator
Messages
9,110
I thought cycling was exactly what the CTEK et al did?
C

It depends on what you mean by cycling. They generally use a float voltage and low current and vary this to induce a shallow cycle. But a deeper cycle is good every few months. Particularly if the temperature is not well controlled.
 

MRichards

Member
Messages
278
I have owned at least one car continuously since 1962 and find it is not easy to destroy a battery. The only casualty was a gel aircraft battery made by Hughes which I allowed to sit around at low charge.
If you have a car which is a garage queen aircraft batteries are ideal since they are designed to have zero current drain. Also,they have a 15 year service life. I found that these batteries are commonly used for standby generators in telephone exchanges so get very little use,however,the telcos are extraordinarily anal & replace them every four years. The trick is to rock up during the change over period & the batteries are free for the asking.
Also,bowling alleys use Odyssey batteries which they replace every two years. These also are generally free for the asking. These are particularly suited for motorsport since they are leak proof & very robust so are not damaged by excessive vibration. They are conventional AGM (glass fibre mat) construction with rubber valves sealing the cells.

Many so-called sealed batteries have a vent line which allows them to lose water. With a bit of ingenuity & good old yankee knowhow (= brute force & ignorance) they can be topped up. Using a hole saw I managed to cut a hole in the top of each cell to fit a fully sealed battery with removable plugs allowing topup.

There is a case for denigrating the use of trickle chargers,however,used properly they do no damage. If you are lazy the float charging Ctek is a cheap alternative.
The Ctek battery conditioning mode has proved useful in recovering batteries which are otherwise cactus fuctorum.
 

Phil the Brit

Member
Messages
1,499
I have owned at least one car continuously since 1962 and find it is not easy to destroy a battery. The only casualty was a gel aircraft battery made by Hughes which I allowed to sit around at low charge.
If you have a car which is a garage queen aircraft batteries are ideal since they are designed to have zero current drain. Also,they have a 15 year service life. I found that these batteries are commonly used for standby generators in telephone exchanges so get very little use,however,the telcos are extraordinarily anal & replace them every four years. The trick is to rock up during the change over period & the batteries are free for the asking.
Also,bowling alleys use Odyssey batteries which they replace every two years. These also are generally free for the asking. These are particularly suited for motorsport since they are leak proof & very robust so are not damaged by excessive vibration. They are conventional AGM (glass fibre mat) construction with rubber valves sealing the cells.

Many so-called sealed batteries have a vent line which allows them to lose water. With a bit of ingenuity & good old yankee knowhow (= brute force & ignorance) they can be topped up. Using a hole saw I managed to cut a hole in the top of each cell to fit a fully sealed battery with removable plugs allowing topup.

There is a case for denigrating the use of trickle chargers,however,used properly they do no damage. If you are lazy the float charging Ctek is a cheap alternative.
The Ctek battery conditioning mode has proved useful in recovering batteries which are otherwise cactus fuctorum.


I'll take you to task on that first sentence. All you have to do is wear a metal watch strap, use a 13mm spanner and touch both between positive and negative terminals. Battery acid in the eyes hurts for quite a while. Ask me how I know.