Leisure battery questions

[ellal]

Thanks for all the replies.

Decided to go for a budget smart charger, and see what happens.

 

[SUNRAY]

It's scrap.
Don't waste any time or money on it.

With respect leisure batteries are supposedly designed to cope with life of charge/discharge rather better than vehicle batteries.

I have been using a pair of 110AH leisure batteries for about 8-10 years for various sound systems and 2 way radio systems. My introduction to them was being asked to clear them out of a hill top radio site where they had been in service in a 3KW UPS until it failed and ran on battery until they reached low voltage cut off. The call out to the failed radio system resulted in the UPS being removed from service: mains in and out and the battery being disconnected. I measured the voltage at something like 1 to 2V per battery. I can't recall the duration they sat there discharged but I'll estimate a couple of years at least.

At home I put them on Lidl 3.8A smart charger which did nothing, pressed the boost and still nothing. Tried 4A conventional chargers and the ammeter just lifted off the stop with instant voltage rise... Generally a sign of knackered battery...
However within a few seconds the voltage started falling and the current started rising, very slowly... generally a good sign.

They both behaved in a very similar way; current and voltage matching quite well and took maybe a couple of days to reach around 10V and 2A or so. Figures which still implied failed batteries. Then I put them back on the smart chargers for maybe a week before they dropped down to a lower charge rate and I disconnected the chargers.

They took around a month to drop fro >14V to close to 13V. I took daily AH readings with an ACT gold tester which gave ~15AH readings for a week or so then a headlight bulb (~4A @12V?) took 1/2 day to reach 6V confirming the 15AH.

2 months down the line I had to make the decision and went for another cycle of: conventional charger, smart charger, rest, test with ACT, discarge with headlight bulb over the course of 2 weeks which gave better results, repeated 2 week cycles saw an improvement each time until the ACT showed 80AH and the bulb giving 30hrs to 6V.

OK that took 6 months and some will say not worth the effort; however I walked past them several times a day and all of the attention took no more than 30 seconds a time. Leading up to 2019 they were used most summer season weekends to run a sound system or a 2way radio repeater for events, since that season they have had only occasional use, (I call it retirement). The batteries are permanently connected to Lidl 3.8A smart chargers to be ready for use.

I've been out tonight baby sitting, on my return home the ACT tester shows: 84 & 81AH. Now the thing about the ACT measurements; it does a pulse discharge test and of course a battery on charge has an artificially high voltage which will rapidly drop by ½V or so and the ACT sees that as the test, in reality if the battery is allowed to rest for a day before the measurement is taken, the readings will be higher, the leisure batteries will typically be 10% giving me around 90AH for second hand 110AH leisures dated 2007 I nearly scrapped 8-10 years ago.

Hardly to be described as

It's scrap.
Don't waste any time or money on it.

Alongside those are 2x 80AH leisures reading 65 & 62AH, so 70AH for 80AH's of about 2012-4 and 2x 95AH car batteries at 45 & 42.5 AH. Vehicle batteries often be 25% higher afther resting so 55AH for 95AH's and around 10% down from last year, these are the final pair of 8 dating from around mid 1990's and 25-30years old. Last July my 3 pairs simultaneously ran 3 school sports day PA systems and very likely may do the same again this year.

Oh and I also monitor the mains consumption for battery charging: 2018 18.7KWh, 2019 19KWh, 2020 8.1KWh, 2021 9.2KWh, 2022 14.6KWh. 20 & 21 of course had virtually no use due to covid and 22 not enough to warrent the 50% increase, accordingly I reckon the car batteries are likely to be retired very soon.


Standing such batteries on concrete.
I never do it. Not even modern plastic cases as they are surprisingly fragile and easily cracked/split. I damaged one 30+ years ago on concrete paying slab by dragging it an inche, certainly not more than 2" and I know of others who put the to similar use to me who have done the same thing and now treat them with similar respect, one will not even let others move them.

 

[Rodders53]

Standing such batteries on concrete.
I never do it. Not even modern plastic cases as they are surprisingly fragile and easily cracked/split. I damaged one 30+ years ago on concrete paying slab by dragging it an inch, certainly not more than 2" and I know of others who put the to similar use to me who have done the same thing and now treat them with similar respect, one will not even let others move them.

<My change of bolds>
That's very different to the urban myth of LA batteries discharging due to being stood on concrete floors.

Not sure any heavy battery is designed to be dragged about. Most 100+Ah leisure ones have lifting handles. I'd suspect that such a small movement was the final straw that broke the already damaged casing. Most batteries aren't transported to multiple locations and on/off loaded, rigged, de-rigged and repeat.

e.g. My caravan one just sits in the 'cupboard' and might be removed from that during a service if the terminals can't be got at for measurements.

 

[SUNRAY]

<My change of bolds>
That's very different to the urban myth of LA batteries discharging due to being stood on concrete floors.

Indeed however many years back we used to stand car batteries on the concrete garage floor and after having a couple go flat during use we reckoned we had to charge them after use and before the next use a week or two later, the smaller sizes which lived on a wooden shelf didn't seem to have the same issue. From that observation it is possible there may be something in the theory, the cold floor could have something to do with it equally it could have been a quality or age issue

Not sure any heavy battery is designed to be dragged about. Most 100+Ah leisure ones have lifting handles.

No these were never dragged about, that occasion was a simple push with a foot to clear a door

I'd suspect that such a small movement was the final straw that broke the already damaged casing.

Possibly but I'd hope not. I'll never know but one of the proprietry battery case repair adhesive/fillers didn't work.

Most batteries aren't transported to multiple locations and on/off loaded, rigged, de-rigged and repeat.

e.g. My caravan one just sits in the 'cupboard' and might be removed from that during a service if the terminals can't be got at for measurements.

I think there may be more which are moved around than you think, as said before I work with sound equipment and maybe 50% of the outdoor jobs I do, such as village fetes, school sports days etc are on battery and my experience of my and my competitors modus operandi are similar, equally temporary/emergency 2 way radio work and what about the hobbies such as model car racing and model boats. Cycle racing and marathons with the start finish arches and clocks etc. Temporary traffic lights etc.The list goes on and on and they all use car/leisure batteries and in my experience they regularly get moved around, shifted in and out of their enclosures etc.

I did have a trailer equiped with 6 car batteries battries and also a set of five in a bespoke wooden structure which usually lived in there for Public Address use and as you say they lived there from purchase to death, all were on wood. All of the loose batteries are always on wood or carpet, once bitten twice shy

 

[ellal]

Just an update, and hopefully a bit of feedback that might help someone in the same situation.

Got the budget smart charger yesterday. On start up it went through a diagnosis, and it came up with 80% charged.
It was interesting watching the charge voltage/charge amperage changing.

After about 12 hours it stopped charging, and the battery now registers 100% full at 13.5V.

So at £23.99 a good investment.

Maybe I could have saved the previous 'dead' car battery had I had one of these chargers!

 

[SUNRAY]

Just an update, and hopefully a bit of feedback that might help someone in the same situation.

Got the budget smart charger yesterday. On start up it went through a diagnosis, and it came up with 80% charged.
It was interesting watching the charge voltage/charge amperage changing.

After about 12 hours it stopped charging, and the battery now registers 100% full at 13.5V.

So at £23.99 a good investment.

Maybe I could have saved the previous 'dead' car battery had I had one of these chargers!

That's looking good but it is the first step in the process, those %readings are unreliable as they sort of give a % of current ability. IE if it's ability is 30Ah then 90% will be 27Ah but working the battery may hopefully regain more of it's original capacity.
The next step is to do a discharge test, something like a headlights bulb and measure the voltage. Initially every 5minutes or so until it reaches about 12.5V then hourly to 10.5V.

Hopefully that should take about 30 hours assuming 4A load. Realistically I'd be happy with half of that for a first test and subsequent tests should improve .

 

[ericmark]

As said I have used the cheap Lidi smart charger for some years now, but the charge completed light does not mean fully charged, if left for some time I watch the built in voltmeter, and consider it fully charged when the voltage has remained static for two days or has reached 13.8 volts. (at the 0.1 amp charge rate) It takes time to recharge the battery, had one which took 3 weeks.

 

[SUNRAY]

As said I have used the cheap Lidi smart charger for some years now, but the charge completed light does not mean fully charged, if left for some time I watch the built in voltmeter, and consider it fully charged when the voltage has remained static for two days or has reached 13.8 volts. (at the 0.1 amp charge rate) It takes time to recharge the battery, had one which took 3 weeks.

3 weeks at 0.1A is 50Ah which sounds acceptable to me for a part discharged battery.

 

[ericmark]

3 weeks at 0.1A is 50Ah which sounds acceptable to me for a part discharged battery.

Due to snow, it was left longer than intended, took off charge today showing 14.2 volts, so around a week on charge. Before the smart charger would not have dreamed to leave on charge for so long.

 

[vonsworld]

I would charge it slowly for a day, then disconnect the charger and most importantly let the battery cool down for a few hours. Then measure the output voltage. There are charts on the internet that give the following capacity levels:
12.89v+ 100%
12.65v 80%
12.41v 60%
12.0v 30%

So if you never get more that 12.0v after cooling it's not in good shape. Sorry.

 

[SUNRAY]

I would charge it slowly for a day, then disconnect the charger and most importantly let the battery cool down for a few hours. Then measure the output voltage. There are charts on the internet that give the following capacity levels:
12.89v+ 100%
12.65v 80%
12.41v 60%
12.0v 30%

So if you never get more that 12.0v after cooling it's not in good shape. Sorry.

Although I've given a vote, I'd probably consider it to be unworthy if it dropped from 13.5-14V down to 12.5V in an hour.

 

[ericmark]

The Lidi charger re-starts at 12.8 volt and switches off at 14.4 volt, so using a wifi linked energy meter I could see what was going on.

Had to photoshop the hours together to show this, and once it goes to 0.8 amp, it changes scale on the energy meter, so could not stitch any more onto it.
the pulses seem to change, showing an old 95 amp hour flooded battery on a Kia Sorento still on the car, and it went to at which point I turned off the charger. Date 11/11/2020 and battery still in use today on the same car. How much is due to car, and how much battery is unknown.

But the Jaguar XE battery a lot newer, and AGM not flooded, and when during colvid that needed charging, as car not used, the energy monitor showed the battery charge rate changing at the same time every day, I assume the engine management computer was sending info back to Jaguar? I know we can pay to be able to start car from phone so the car is warm before we go out to it, never used it so stopped paying for service.

There is a big difference in charging the 12 Ah AGM in the jump starter, to the 90 Ah AGM in the Jag, or the 35 Ah AGM in the mobility scooter, but using the energy monitor each of the chargers seems to show very similar patterns.

And they all say battery fully charged, but the energy monitor is still showing the charge rate is gradually altering, well pulse width and space width, as rate stays constant, and on the Lidi charger the battery voltage is still raising even with a 0.1 amp charge rate with a 40 Ah battery on the Jazz, so clearly still charging.

I remember many years ago in the 70's when studying auto electrics being given a home work, what seemed a simple question, why does the battery voltage go down.

But look at the tables for voltages between to metals, and these seem to be fixed, the Daniell cell is used with a comparator to measure voltage as it is so stable, no internet back then, so it was into the collage library, could find loads on the Leclanché cell, but nothing on lead acid, so had to take a guess, I got 9 out of 10, rest of class were getting no more than one mark, but not really a fair question when there was nothing in the collage library, however it sparked an interest in batteries.

In Algeria we would get dry charged CAT batteries and non charged local batteries, the latter would take a full day to charge after filling with acid, it was quite a balancing act ensuring I had a charged battery ready for use, but until filled they would last for ever.

However the time taken to charge a freshly filled battery was always a problem, it took a good 24 hours unless dry charged, so even back in the 80's I realised the time problem with charging batteries.

I did come across some gel batteries designed to power the heaters on the valves in radios, but back then battery chargers were a bit crude, a bulb and a metal rectifier, not even a transformer, and one used a hydrometer to work out when charged.

In the late 70's Lucas came out with the sealed battery, it had a venting system to reduce water loss, but it was not AGM, it was just they used excess acid, also it seems a material was used to help stick the spongy lead to the plates, and this caused gassing, so spreading it more even could reduce the gassing and need to top up. But the alternator which had a fixed voltage of 13.8 volt rather than the dynamo which open circuit setting with a two bobbin regulator was 16 volt, also reduced water loss.

To day when charging the Jag need to correct to jump start point under bonnet even when battery is in the boot, so the engines computer can monitor the charge. It is clear when battery 90% charged or more, as engine cuts out at junctions, if battery is low, the stop start is inhibited.

But at least if a lead acid battery is damaged in a crash, it does not burst into flames.

 

[SUNRAY]

... But at least if a lead acid battery is damaged in a crash, it does not burst into flames.

And that last line is becoming a problem for our emergency services.

The short circuits caused by crumple zones doing their job on the unfused circuits is still there, however I think it's unlikely the designers can solve every possibility.

For my portable work I used to bolt a 30A fuse to, and insulate, the +VE terminal. That was as a result of one of our BT vans being involved in a collision and the starter cable starting a fire.

 

[ericmark]

I was thinking about EV's and how they takes days to put out fire.

 

[SUNRAY]

I was thinking about EV's and how they takes days to put out fire.

Yes I got your comment thank you, as it happens I was explaining to Missus Sunray a few days ago when we saw 4 traffic oficer vehicles on hard shoulder and closing off first lane, 1/2 mile later a 23 reg Tesla with AA van and 2 fire appliances in attendance and what looked like a big canvas bag being unfolded.