New battery...

[JohnG]

5 hours ago, PodOne said:

But surely bigger is always better!

'Ti's true, Clarkson said so . . . 

[SirHector]

I too love having those extra ooomp tho lol

Edited March 10 by SirHector

[Andy Moltu]

Big may be better but, as ever, the law of diminishing returns applies.

You need enough spare capacity to cope with cranking when you have to for longer than you expect  and for when you have problems or to get you home when the alternator fails.

[SpitFireSIX]

Hi,
I've always tried to fit the "Biggest" SLI battery that will fit. I then compare the CCA/Ahr cost and make my choice.
I want high Ahr so that I have more reserve capacity then I will ever need; at least three times in its life the starter motor has moved the car several meters out of danger.
Generally, the higher the CCA the more Amps the starter motor will pull as the internal volt-drop inside the battery will be lower so therefore the starter-motor voltage will be higher?

I found an AGM battery online for £76 a couple of years ago,. very low self discharge & battery terminal voltage stays higher than any standard battery I have seen. I have a "modern" A114 alternator that puts out 14.4-6 volts at idle with all electrics on. I have fitted a diode to bump the voltage up under-load 200mV. I am not driving for long times at the moment so I believe the voltage is OK. I plan on fitting some logic to the alternator so that I can adjust the output voltage between 0V/13.8V/14.9V. 14.9V during braking/deceleration? 

I have a £15 battery monitor fitted for data logging. Logs every 2 minutes or 100ms when in scope mode. The volt-drop during starting gives me a metric for internal resistance.

Cheers,
Iain.

[Keith66]

On 1/25/2024 at 12:44 PM, Hawk said:

Always use Halfords - they price match, I can usually walk out with what I want and they have a physical location that I can take 'duff' batteries back to.  

We all need to be aware of this.

Yes you can often save a few quid online but come 10 years or so after more and more buy online and people like Halfords don’t exist or just have a few stores in the big cities things might get difficult if you need something now or want to touch and feel before buying.

Si I always try to buy stuff from someone with a physical shop, if I can, so just got a microwave from Curry’s and they price-matched Amazon.

Then had to get a new vacuum cleaner an elderly relative she wanted to try different ones and you can’t do that at Amazon or AO. So popped down to Currys (again) to try stuff out and choose one. Again they matched AO. Ok it was three quid more but on £150 ish not to bad, not even a pint!! (or half on the south east)

Cheers  Keith

[Richmac]

On 4/1/2024 at 10:44 PM, Keith66 said:

We all need to be aware of this.

Yes you can often save a few quid online but come 10 years or so after more and more buy online and people like Halfords don’t exist or just have a few stores in the big cities things might get difficult if you need something now or want to touch and feel before buying.

Si I always try to buy stuff from someone with a physical shop, if I can, so just got a microwave from Curry’s and they price-matched Amazon.

Then had to get a new vacuum cleaner an elderly relative she wanted to try different ones and you can’t do that at Amazon or AO. So popped down to Currys (again) to try stuff out and choose one. Again they matched AO. Ok it was three quid more but on £150 ish not to bad, not even a pint!! (or half on the south east)

Cheers  Keith

+1

[Paul J]

On 4/1/2024 at 10:44 PM, Keith66 said:

We all need to be aware of this.

Yes you can often save a few quid online but come 10 years or so after more and more buy online and people like Halfords don’t exist or just have a few stores in the big cities things might get difficult if you need something now or want to touch and feel before buying.

Si I always try to buy stuff from someone with a physical shop, if I can, so just got a microwave from Curry’s and they price-matched Amazon.

Then had to get a new vacuum cleaner an elderly relative she wanted to try different ones and you can’t do that at Amazon or AO. So popped down to Currys (again) to try stuff out and choose one. Again they matched AO. Ok it was three quid more but on £150 ish not to bad, not even a pint!! (or half on the south east)

Cheers  Keith

  I have recently had an issue with Halfords and most disappointed with the customer service. My battery, a Halfords 096 with a 3 year warranty failed to start the car with only 7 volts on the voltmeter. Along with the receipt (which is within the warranty term until June) and the Battery I called at my local Penzance branch, Stuart the Halfords assistant tested my battery and said its shot and I need a new battery, I offered him my receipt and was told the warranty only covers a factory fault failure. I was most annoyed and explained a factory fault has occurred as the battery failed within the warranty term.

  I also contacted customer services 3 consecutive days and was told our team is sorting it out, this was two weeks ago and to date I have received no response whatsoever. Halfords are not a good supplier in my opinion and I will never use them again. I have now given up as it was causing me unnecessary stress. The battery was bought at a premium price with a 3 year warranty which Halfords will not honour.

Paul 

[SpitFireSIX]

1 hour ago, Paul J said:

  I have recently had an issue with Halfords and most disappointed with the customer service. My battery, a Halfords 096 with a 3 year warranty failed to start the car with only 7 volts on the voltmeter. Along with the receipt (which is within the warranty term until June) and the Battery I called at my local Penzance branch, Stuart the Halfords assistant tested my battery and said its shot and I need a new battery, I offered him my receipt and was told the warranty only covers a factory fault failure. I was most annoyed and explained a factory fault has occurred as the battery failed within the warranty term.

  I also contacted customer services 3 consecutive days and was told our team is sorting it out, this was two weeks ago and to date I have received no response whatsoever. Halfords are not a good supplier in my opinion and I will never use them again. I have now given up as it was causing me unnecessary stress. The battery was bought at a premium price with a 3 year warranty which Halfords will not honour.

Paul 

Hi,
I believe a faulty battery must be returned full charged so they can test it.  EDIT.
"A battery showing a resting voltage of less than 10.5v will have become discharged through one of the above points, this is not a manufacturing fault."

Just relaying what I have read. Somewhere. See #7 below
Cheers,
Iain.

PS. From Tayna Website:

What Voids the Warranty:
1 - Abuse, misuse, improper installation, improper maintenance and modifications including removal of the battery lid.
2 - Incorrect application.
3 - Physical damage, including broken or melted terminals.
4 - General wear and tear.
5 - Unserviceable as a result of improper charging.
6 - Failure due to overcharging, deep cycling, sulphation and undercharging are not covered.
7 - Voltage less than 10.5v (battery fully discharged).

Edited April 5 by SpitFireSIX
Added PS

[Paul J]

17 hours ago, SpitFireSIX said:

Hi,
I believe a faulty battery must be returned full charged so they can test it.  EDIT.
"A battery showing a resting voltage of less than 10.5v will have become discharged through one of the above points, this is not a manufacturing fault."

Just relaying what I have read. Somewhere. See #7 below
Cheers,
Iain.

PS. From Tayna Website:

What Voids the Warranty:
1 - Abuse, misuse, improper installation, improper maintenance and modifications including removal of the battery lid.
2 - Incorrect application.
3 - Physical damage, including broken or melted terminals.
4 - General wear and tear.
5 - Unserviceable as a result of improper charging.
6 - Failure due to overcharging, deep cycling, sulphation and undercharging are not covered.
7 - Voltage less than 10.5v (battery fully discharged).

Well it does not leave a lot to warrant. My Battery had been well cared for it still failed within the warranty term, as far as I'm concerned it should have been replaced. How can Halfords say or prove that any of the above issues is relevant to my battery.

[RobH]

1 hour ago, Paul J said:

Well it does not leave a lot to warrant. My Battery had been well cared for it still failed within the warranty term, as far as I'm concerned it should have been replaced. How can Halfords say or prove that any of the above issues is relevant to my battery.

If the battery has self-discharged due to some internal current leakage, that is a manufacturing fault.   The problem is how do you prove it ?    As you say, the warranty is very limited in scope but a battery is so open to poor treatment by the user that it probably has to be written that way. I suspect the onus of proof is on you to show it was not mistreated, not on the supplier to show that it was.  

Did you try to charge the battery on a separate charger?  If it will accept a charge and hold it once disconnected then the fault isn't the battery, however if it will accept a charge but loses it again after a while there must be an internal leakage.  If it won't accept a charge at all then you can't prove anything either way. 

 

[Motorsport Mickey]

Would connecting in series with a good battery allow it to be charged then ?

Mick Richards

[RobH]

54 minutes ago, Motorsport Mickey said:

Would connecting in series with a good battery allow it to be charged then ?

No, that would over-charge the good battery and no 12V chargers could do it anyway because their maximum voltage is too low for 12+7.  

If the battery draws too much current from a charger initially,  you  could use a 12v 21W indicator bulb in series, to limit the current.  On 5v (12-7) that will pass about 1A* which would be a good slow charging rate.  Once the battery voltage gets up to something sensible it can be connected direct to the charger

 

[* the resistance of an ordinary bulb varies with how hot the filament is. If under-run on a low voltage the resistance is rather lower than when hot with the full voltage applied]

 

Edited April 6 by RobH

[SpitFireSIX]

7 hours ago, Motorsport Mickey said:

Would connecting in series with a good battery allow it to be charged then ?

Mick Richards

Hi,
Putting two batteries of differing state of charge (SoC), i.e. one at 100% & one at -0% will just flatten the higher one. Short term it might enable a car to start or a Smart-charger to begin charging. A smart charger will not charge a battery below 0% SOC. An analogy would be running a diesel generator below 0% fuel & expecting it to still function correctly after a refill. 
 

A car battery Voltage off load span of 100% SoC is only around 2V. 100% SOC is around 12.7V. 0% SOC is around 10.7V.
So less than 10.7 is less than empty.
Charging a fully charged battery at around 13.8V. Floating. should not gas and be 100% SOC & ready to supply current when needed. Standby voltage will ensure very long life, greater than spec.
If you connect a 100% SOC 60Ahr battery for example to a power supply that is at around 13.8V and increase to 14.5V the current will increase to around 0.5A, if it is more than this battery was not 100% SOC. Continued charging at over around 13,8V will just generate HO2 gas that will have to replenished as water.
 

I worked for an EV conversion company that destroyed/destroy  1000's of Lead Acid automotive batteries. They were able to claim warrantee! Unbelievable but true.
I wrote the Software for charging. They refused to spend £50 on a current transformer, so I had to write SW to only charge at 27.6V (2 x 12V) to prevent gassing. 
 

Cheers,
Iain.

[Paul J]

On 4/6/2024 at 2:18 PM, RobH said:

No, that would over-charge the good battery and no 12V chargers could do it anyway because their maximum voltage is too low for 12+7.  

If the battery draws too much current from a charger initially,  you  could use a 12v 21W indicator bulb in series, to limit the current.  On 5v (12-7) that will pass about 1A* which would be a good slow charging rate.  Once the battery voltage gets up to something sensible it can be connected direct to the charger

 

[* the resistance of an ordinary bulb varies with how hot the filament is. If under-run on a low voltage the resistance is rather lower than when hot with the full voltage applied]

 

Hi Rob

To update I had the battery on charge for a week and slowly over 6 days it gradually recovered, it's now on a Lidl conditioner and is holding out on 4 bars and 13.1 volts. Tomorrow I will let it rest and see if it holds the charge, I need to have confidence in the battery before refitting. Thanks for all the helpful advice.

Paul

[SpitFireSIX]

Hi,
If you have a smart phone i would buy a £15 battery monitor & fit to battery. long term data would show any problems. I have a monitor on every battery I own.
Measuring the energy capacity & internal resistance  would give you an insight. Checking Ahr/Capacity is not so easy, a bit like checking a match works. 
You could also return it under warrantee & let them tell you it is OK? 

Cheers,
Iain.

[Hawk]

11 hours ago, SpitFireSIX said:

Hi,
If you have a smart phone i would buy a £15 battery monitor & fit to battery. long term data would show any problems. I have a monitor on every battery I own.
Measuring the energy capacity & internal resistance  would give you an insight. Checking Ahr/Capacity is not so easy, a bit like checking a match works. 
You could also return it under warrantee & let them tell you it is OK? 

Cheers,
Iain.

Do you have a link for the monitor you use ...recommendations always welcomed

[SpitFireSIX]

2 minutes ago, Hawk said:

Do you have a link for the monitor you use ...recommendations always welcomed

Hi,
eBay item number:295644935211

The price keeps going up. I would offer him £15 as that's all I have been paying him.

Cheers,
Iain.

[RobH]

Apart from having a logging function, that gizmo won't tell you any more about the battery than does the voltmeter already fitted to your car (and much less than an ammeter can ) .  

 

[Motorsport Mickey]

11 minutes ago, RobH said:

Apart from having a logging function, that gizmo won't tell you any more about the battery than does the voltmeter already fitted to your car (and much less than an ammeter can ) .  

 

But it can do it whilst you have breakfast telling you if the car will need a boost to get started ?

Mick Richards

[Steve-B]

I guess for some the aforementioned device might have some redeeming value but for me its Silicon Snake Oil (credit: Clifford Stoll) as as proper trickle charger has an indicator. I for one like going into the garage just to look at the display on mine

[stuart]

Or an even cheaper one Battery monitor

Stuart.

[Keith66]

On 4/5/2024 at 6:18 PM, Paul J said:

Halfords are not a good supplier in my opinion and I will never use them again. I have now given up as it was causing me unnecessary stress. The battery was bought at a premium price with a 3 year warranty which Halfords will not honour.

Hi All

My point was not a recomendation of Halfords or any supplier in particular just a point that if we do buy everything online to save a couple of quid one day that will be the only choice.

Less of an issue with specific parts that fit specific cars but not much fun if you are buying stuff you want to touch or feel before deciding what to buy.

Cheers  Keith

[keith1948]

On 3/10/2024 at 11:25 AM, RobH said:

OK - 'naysayers' turn .  I don't doubt that your big battery works well for you, but have you actually tried a standard size? 

I know I'm (figuratively) wasting breath but let's do some simple arithmetic for the benefit of others.

First a fact -  The current drawn from a battery when starting is determined by the starter motor, not by the battery. If you have two car batteries - one larger and one smaller - both in the same state of charge, the the starter will pull exactly the same current from either. 

For the sake of argument let's say you have a pretty inefficient starter motor and your engine is super-high compression so it needs 300 Amps to crank it over. Let's also assume your engine is in pretty poor tune so it takes a whole 2 minutes of continuous cranking before it will start.

That is  300 x 2  ampere-minutes which equates to 600/60  =  10 ampere-hours .     As a rule of thumb cranking should take only a quarter of the full battery capacity so a 40Ah battery will do everything you need even for that extreme case.  

( In reality with a decent engine, draw may be 250A for 20 seconds equivalent to 0.14Ah  -  why would you 'need' a 100Ah battery? )

If the starter draws 300A when starting under cold conditions because the oil is thick, the battery needs to be able to supply 300CCA.  The starter just cannot draw any more, so higher CCA capacity will never be used.

By fitting a larger battery than necessary you are wasting money on capacity you will never need, and lugging around excess weight which is essentially useless to you.  The only time extra capacity may be of use is at the end-of-battery-life, when the larger one may continue to work for a few more weeks until the excess also fails.  

 

 

 

Thank you Rob for explaining the mysteries of Ah and CCA. I am just looking at replacing the 6 year old Tungstone battery in the TR. This was one bought in an emergency situation so I just went for a battery that would physically fit and had terminal orientation type 1 (Terminals engine side with + on drivers side). The old one is 078 size 55Ah and 490CCA. Size approx 170w 180h 235l

According to other postings, the terminals should be next to the bulkhead for TR's up to the 4A. Personally I prefer them engine side as in TR5 onwards - less chance of connecting a spanner between the + and bulkhead from experience. Just need to make sure the earth strap is long enough. Someone posted somewhere that it is 'safer' to have the terminals next to the bulkhead in case you have an accident and the engine is pushed back onto the battery and the fixing rail shorts out the terminals. Don't understand that argument since if the engine is pushed back 4 or 5 inches I think I might have other things to worry about!

Halfords do a HB072 battery with 68Ah and 600CCA with terminals correct for me but at £120 a tad expensive and would by your calculations be over spec. A Yuasa Ybx3214 has 60AH and 540CCA for £64. GSF have a Yuasa ZA042627 (type 072) 72AH and 600CCA for £103.

Halfords do a HB063 41AH and 360CCA for £45 but terminal position is type 0 so wrong way round for me.

I should add that I have a high torque starter.

I have charged up the old battery using a Halfords smart plus charger that is supposed to 'condition' as well as charge. It now starts the car but not sure whether it is near end of life. How would I check this?

Keith

 

[RobH]

1 hour ago, keith1948 said:

not sure whether it is near end of life. How would I check this?

A battery will slowly degrade throughout its life, losing capacity as the plates degrade- mainly through sulphation . How much is lost cannot  be found just by measuring the voltage, because the cells still charge fully as they should. All that has happened is that the usable area of the plates is less than it was originally, meaning it cannot supply as high a current as it did  and not for as long .  None of the cheap electronic devices (circa £50 or less) sold as 'car battery testers' are really any use as they can't check this - basically they are just voltmeters which will tell you the state of charge; nothing more than you can learn from a DVM.  

The only proper way of checking battery capacity (Ah) is to discharge at a set current and record how long it takes to reach the fully discharged state.  The way to check internal resistance which affects CCA is to draw a large current and measure the drop in voltage - garages used to have simple  devices which gave an approximate indication of this, basically a meter and a large resistor which got very hot.  Nowadays there are cleverer methods which measure conductance using small a.c. signals but testers like that cost a fair amount that only a garage can properly justify. 

The simplest way for you to check is to find a friendly garage with one of those meters and ask them to do a measurement for you, perhaps as part of a service or when you have the  MOT.

 

 

 

Edited 3 hours ago by RobH
typo

[keith1948]

Thanks Rob

As well as 'standard' batteries, Halfords supply what they describe as lead acid batteries. They have a couple of Yuasa batteries, YBX 3205 and YBX 3214 that have 60AH and 540CCA for around the mid £60 mark. Only difference is terminal positions. These have slightly more Oomph than the old one in the car so on the basis of your calculations would probably be fine. Certainly less expensive than the calcium or 'standard' offerings.

Keith