Red top still good battery to get ?

[mad_pete]

My defender spends a lot of time on charge on the garage. Recently the c tel charger is reporting fully charged but starter runs like it’s flat (clicking only) but if unplug and re plug the charger in a few hours it will run. Next few weeks while on charge back to flat.  Might be charger or battery I guess but either way I expect the battery is toast now. Is a gel agm red top. They still good? Just grab another of those ?

[Snagger]

I read an awful lot of comments suggesting Optima quality plummeted a decade or so ago.

Excide and Varna still seem to have good reputations, and my Banner cheap commercial batteries were very good.

[Nonimouse]

Would only fit Optima if they were free. Had so many issues with them on clients vehicles

I like Numax, part of Lucas.  Never had any issues with the XV range of deep scylce marine starter batteries

[simonr]

Optima Yellow & Blue are (were, at least) OK.  Red were just a cheap version that were pretty rubbish from the start.

The problem with them (all of them) is you need to take care of them - they are sensitive to under / over charging.  When they were first launched, it was almost impossible to find a battery with as high a discharge current.  However, that changed quickly.

Hawker Odyssey batteries still are great - but like Optima they are sensitive to abuse.

Numax on the other hand will just eat up abuse.  They are way cheaper than either of the above and perform better under most conditions.  The only negative is they are a flooded (wet) cell battery which will leak if you turn it upside down.

For most applications, Numax wins!  Where it doesn't, these days I'd use LiFePO4 batteries.

[simonr]

6 hours ago, mad_pete said:

My defender spends a lot of time on charge on the garage.

Continuous trickle charging is a great way to kill batteries!

But, wait a minute, some battery manufacturers sell trickle chargers?  Hmmm....who stands to gain if you buy a product which gradually kills the battery over a year or two?

Best option is a regular battery charger on a time switch.  Set it to charge for 30 mins every 7 days (adjust this as needed).  The batteries benefit from a strong current flowing through them, kind of like blowing the cobwebs out of them.

[mad_pete]

I had a wet battery and can say it does come pour out when upside down. so looking for something gel like.  What is a good V8 size ? I have a Rover 4.2 and hydraulic winch.   LiFePO4 smaller footprint sounds good as long as they aren't crazy money. I want to squeeze some more things in that underseat area.

[FridgeFreezer]

I'd look at the various stop/start AGM batteries from grown-ups, for example:

https://www.yuasa.co.uk/batteries/automotive/ybx9000-agm-batteries.html

There's Bosch, Varta, etc. too all available from standard motor factors with 3-5 year warranty.

Doesn't take much to start a V8, I ran a scrap battery from an Austin Metro for a couple of years

[smallfry]

Optima ........ All fur coat and no knickers, and they dont last long either.

[Badger110]

On 8/15/2022 at 8:13 PM, simonr said:

Continuous trickle charging is a great way to kill batteries!

But, wait a minute, some battery manufacturers sell trickle chargers?  Hmmm....who stands to gain if you buy a product which gradually kills the battery over a year or two?

Is it the same as leaving your battery wired up to a solar panel all the time?

[rusty_wingnut]

got three Red tops, one approx 12yrs old now and still working. ironically it's been abused starting crappy old tractors fairly irregularly.

[simonr]

44 minutes ago, Badger110 said:

Is it the same as leaving your battery wired up to a solar panel all the time?

A bit more explanation!

Sulfonation occurs in batteries when they are stored at less than 100% charge, when they are overcharged, when the temperature is high and when you use a battery as normal.  Charging reverses this process & converts the Lead Sulphate back to metalic lead, Sulphuric Acid & Oxygen.

If you fully charge a lead acid battery, then keep it on trickle charge such that the charge rate accurately matches it's self discharge rate - it will be fine.  Unfortunately, this is rarely the case.  It's put on trickle charge at less than 100% and often never quite gets there.

When the charge current is too low, there isn't enough energy to reverse the Sulphonation reaction & restore the battery.  If it's trickle charging and ends up hovering below 100%, the trickle charge will often make the situation worse.  When you start the car, it's close enough to 100% that there isn't time for the high current from the Alternator to reverse the Sulphonation process.  It just builds up over time until it's non reversable.

Lettinng the battery self discharge over a few days, then giving it a high current charge is more likely to reverse the reaction, even if the average state of charge is slightly below 100%.

I would avoid simple Solar & Trickle chargers & instead use a properly managed charger - or a less managed charger on a timeswitch.

At work we use red tops, dozens of them for powering stuff.  We use Noco Genius 10 chargers - and just charge them all periodically.  They seem to last pretty well.  When they die, it's usually through physical damage rather than Sulphonation!

[Happyoldgit]

I use a Noco Genious 10. Good bit of kit.

[FridgeFreezer]

CTEK (£££) and Optimate chargers have a de-sulphation phase that blasts a higher voltage up the battery to knock the gunk off, I've rescued a couple of batteries with mine many moons ago.

I never really like leaving stuff on trickle though, I don't trust it not to somehow start a fire - and batteries just stored charged are usually pretty happy. Our ambulance stays parked for months at a time, battery cutoff removed, and so far has been pretty kind on batteries apart from when I didn't leave the cutoff cut off and it all got down to 0v over a period of months

[Nonimouse]

1 hour ago, FridgeFreezer said:

CTEK (£££) and Optimate chargers have a de-sulphation phase that blasts a higher voltage up the battery to knock the gunk off, I've rescued a couple of batteries with mine many moons ago.

 

I've used that ability on the CTEK to 'save' quite a few batteries, including a yellow top optima. It's quite useful

[Escape]

As above, Ctek is not cheap but can pay itself back if you can revive a few batteries. And they're quite durable, I ran over my old one with a Range Rover once, it just kept working (no longer waterproof though).

I have seen batteries suffer when left connected to (cheap) trickle chargers. All my batteries, in or out of cars, are stored with an occasional (i.e. when I remember) session on the Ctek and charged when needed. Seems to work OK.