Does charging your car battery on fast charge damage it?

Post Office? Telephone exchanges used to have racks of lead acid batteries to provide the DC voltage down the phone lines that drove the telephone handset in case of mains failure and hence loss of the normal supply.

Old Post Office joke: Each telephone exchange was manned overnight by a man and a dog. The man was there to fix the equipment if it went wrong. The dog was there to bite the man if he attempted to fiddle with the equipment.

Andrew

Good thread - good question.

My 35 year old Halfords charger produces a lower voltage than the alternator, measured in the car and at the battery; so I figure its fine to leave it on "high". The current drops to less than 1A when the battery is charged, so the battery is not cooked.

My car is an SMAX with a 2.0 diesel and a huge battery. It can still randomly flatten the battery, its a Ford thing apparently. Anyhow numerous recharges doesn't seem to have done any damage .

I have an Odyssey battery in my Disco; they come with a warning about low drain on the battery irreparably sulphating the plates.
This is particularly the case with modern cars, full of electronics, where turning off the ignitions doesn't kill everything.
Remote door opening, alarms clocks, ECUs etc all play their part.

Without a drain, the batteries can be stored for a couple of years, without issue.

"Prolonged storage of vehicles with fuel injection computers, alarms, GPS and other
electrical devices that require continuous battery power to support active memories;
this power drain must be offset with a maintenance-float charger, periodic charging
or disconnecting the battery to prevent the establishment of irreversible crystallized
sulphation in the battery plate oxide. Failure to address this destroys battery capacity
and voids the warranty, as this is not a warranted defect in materials or workmanship."

Bill

Andrew,

Your quote re man & dog in telephone exchanges is slightly wrong. The man was there to feed the dog, not look after the equipment! Otherwise, as you say, the dog was there to keep the man away from the equipment.

On a slightly more serious note, back in 1969 I took over the maintenance of a small Strowger exchange. My predecessor had been having trouble with the charging panel and hence started adding a bit more charge via the ampere-hour meter every time he visited. I carried this on. One Friday am, I made my customary visit, all ok, so advanced the A-H meter a bit and went away. Went on holiday for three days, came back, and as far as I knew all still ok. The next Friday I made my customary early morning visit only to find that instead of the customary load sharp clatter of the exchange, all was muffled, as if wrapped up in a blanket. Checked the voltmeter - "Oh bxxxxy hxxx" - it's down at 46V. Now this was a suppessed zero thing so I removed the cover and moved the arms down. The needle followed it. My guess is that the battery voltage was below 40V (it should have been 46v & 52V) and the rectifier had failed to switch on. Manually switched on the rectifier, a loud bang as the contactors operated, and a deep, loud buzz followed, but it worked. Rang the boss to let him know - end result was a temporary charger arrived pdq, followed by a new control panel and an extra rectifier a few days later. And the battery? That poor old hardworking, much abused device? Well the specific gravity was off the scale - downwards. 1/2 inch later (we had to record the specific gravity monthly) it appeared back on the scale and over the next 18 months slowly climbed back towards where it should have been.

I suspect I was within a few hours of having an exchange isolation on my hands. Which, in those days, was almost a candidate for a question to the P.M.

FWIW, the exchange was left for a week without a visit. In theory, exchanges of that type were designed to more or less look after themselves so a week without a visit should have been totally satisfactory.

Peter G. Shaw

My experience of lead acid batteries Bill is not so as regards storage ! The only way to store them is dry ! On one notable occasion a new battery was fitted to a classic tractor started once and left for a year or so, the battery was scrapped after numerous attempts to recover it proved fruitless- there was nothing connected to the battery ! It might have been a good candidate for EDTA treatment ? But modern vehicles yes all those milliamp drains will over time kill a battery DEAD ! Noel

Andrew’s recent post about telephone exchange maintainers and their dogs, and later Peter Shaw’s account of his dalliance with what I suspect was a UAX13 type exchange remind me of my own experiences. I joined PO telephones in 1963 and left B.T. in 1996, I spent the majority of my time with them maintaining exchanges, with a a significant period of that time looking after some smaller, rural ones, UAX 13, 14s and later TXE2s on my own (although I did take our black Labrador to work on occasions).

Whilst we were very well trained to be able to locate and repair faults in the switching equipment, most of us had only a sketchy idea about the power plant and relied on the expertise of the “power group’ to deal with any significant problems.

The power system in place in the exchanges when I first started work in them was to have two batteries, one charging and the other “floating” the exchange with, if I recall correctly, a nominal 24 hour turnabout. The problem with this system was that the battery just about to be switched in to run the exchange was significantly, often two or three volts, over the nominal 50 volts that the exchange required. To deal with this a battery of “counter emf” cells were wired in series with the main battery, these were alkaline cells with a nominal voltage of 1.1 volts, connected in reverse polarity and they were short circuited by the switch gear only being brought into use by removing the short when the battery voltage was too high. As you might imagine, these batteries objected quite violently to this treatment and used to “boil” when in use, so much so that a layer of oil was sitting on top of the electrolyte to prevent frothing. As exchanges grew bigger the power demand increased and bigger main batteries were installed, although the counter emf cells remained unchanged. This resulted in even more violent boiling and the oil layer was replaced by plastic “pebbles” to try and collapse the froth that built up. The switchgear to achieve the control of this system usually consisted of some chunky copper “shoes” moved into and out of position by a worm drive.

Much to the relief of everyone involved, improved power plant design did away with all of this and a system known as “end cell switching was installed in all of the exchanges I looked after. This had a battery kept fully charged by a rectifier which followed the load demanded by the exchange and regulated the voltage to close limits of the required 50 volts. If a mains power failure occurred, then the “end cell” which was isolated from the main battery and separately charged by another rectifier, was switched in to replace the high level of charge initially existing as the main battery moved away from the highest point of the discharge curve. After that, if there was an engine driven generator installed that should take over, if not then a “phone call to the “power group” would get you a portable generator to connect to.

Don,

Quite right, it was indeed a UAX13, in my view possibly the most reliable of all the Strowger type exchanges. And yes, power plant knowledge was indeed limited to topping up the cells and recording the specific gravity of the pilot cell so as long as the power plant worked, it was left severely alone. I suppose, even removing the cover and adjusting the arms of the suppressed zero voltmeter was a no-no. Still, until today, no-one knew about that!

Although I also had a UAX7 to look after, I never got to work on a UAX14.

Black Labrador. We had one - big, greedy, lazy, ugly (for a Lab.), stinky breath, but absolutely 100% Labrador temperament. Lovely dog.

Peter G. Shaw

Yesterday [i.e. 7 days later] , the Battery was flat as the proverbial pancake … but it’s a good brand, and only a couple of years old.

You may be lucky Michael, but my experience with a battery that had been totally exhausted followed the manufacturer line that this causes premature demise. In my case it was the habitation battery on a new motorhome that, unknown to me, had a split charging fault. While the fault was rectifed reasonably quickly after the dead battery episode, the battery never recovered & was replaced under warranty in under a year due to lack of capacity. As the motorhome was built to my order & delivered less than a fortnight after it left the production line, the battery would have been a fresh one from the manufacturer.

Bosch/Varta batteries seem to last very well.

Indeed - my usual "go to" brands. Both are Johnson Controls brands & likely the same batteries with different badging, though Bosch usually sell for less than Varta equivalents. Yuasa can also be good, but there are Yuasa and Yuasa - "OEM" Yuasa motorcycle batteries can carry different codes to "replacement" Yuasa batteries recommended for the same application. Had this with my wife's Honda VTR 1000, where only an OEM battery bought from a Honda dealer performed as expected. Strangely the OEM battery was cheaper than the "replacement" alternative that didn't perform as well.

EDTA has been known to give a couple of years of extra life, so is worth the effort.

IIRC EDTA dissolves the lead sulphate & this can clear plate shorts where the shed deposits have built up at the bottom of the cells. But the lost material is still lost & capacity is reduced. From my POV, it would not be worthwhile to spend time & money on either the reach truck or the ride-on sweeper at work trying to extract a bit more "life" using EDTA - we are aware that the batteries are well past their best, that they have a high rate of self-discharge & much lower than new capacity. But they can currently perform to the low usage requirement expected of them. Should the usage change to be required to run a full shift on a charge, then EDTA will not restore that level of performance & the MD will have to reach deep into his pocket to get them re-celled.

Nigel B.

Dry new cells installation: I got a scare

So once in my working life I had to deal with the replacement of a battery(Huge cells). I was a safety officer OHASA as well. So here come the contruction team and start rigging the rest of the battery room to take the new batch of dry cells.
Brand new cells were installed and then the fun started. One constrcuction worker start pouring the battery acid-liquid into the new dry delivered cells. A huge mist filled the room and these cells temperatures rised as it reacts with the plates. I could not believe my eyes, and immediately evacuate the personel from other rooms as well as the construction guy. On the phone to the boss, on his phone to more bosses. It then came back the the construction guy must continue carefully, this happennes apparently if there is a big difference between dry charged new cells and the liquid filling them again. I am not an expert here, that was the reply back. The battery room did have two large extractor fans no sparks insulated types. Too much for them.

It took the cells to stop misting lets say since 10:00 in the morning to around 18:00 that evening, then they started to cool down slowly......In the end everything settled and worked till the place were scrapped for new equipment and smaller battery/rectifier units. As far as I am concerned this was not a normal situation, no smoking.

Edited By Chris Mate on 26/11/2021 16:31:28

Over the past few months, the Stop `Start function of my Renault Clio 4 had stopped working with a fault message displayed on the console.

The car went in for its service and I happened to mention this "fault". The garage rang me to say the battery was on its way out and the car's logic had disabled Stop Start - did I want a new battery ? They quoted a price which I accepted. The battery was an original and just under 8 years old, so its been a good battery in its lifetime.

I have just paid the bill - no great surprise however attached to the bill was the battery test printout:-

48% Health of battery

47% Charge of battery

12.26 volts at state of rest

Perhaps I should have waited to replace the battery and used up a bit more of its life, but as batteries can fail when old, and living in the countryside, thought it wise to replace it. I doubt I will buy another one for this car.

Bob

MANY years ago, ran a very secondhand Ford 100E (Had a vacuum tank which would support a wiper motor powering two arms The vans had only one at first )

The Shrewsbury works tmotor club had a deal set up with a company in London, and since the staring method was already me and staring handle, when visiting parents in north London, drive to east London for the new battery.

Stopped on the front, and went in "Bring it in" , but battery was SO dead that would not start off the handle. The third cell failure was too much!

In contrast, our late 2005 Toyota Yaris battery was still functioning well after 12 years, despite being smaller capacity and having a far greater electrical load than the 100E! The march of progress in materials and control systems

Howard.

Our company operated a private micro link between Longbridge, Cowley, Swindon and London, we covered the maintenance of the Cowley and London equipment and the relay at Christmas Common to get over the Chilterns, the route to Swindon was also via Christmas Common. When I joined the department that covered the maintenance of this equipment I didn’t realise that an excellent pub was next to the Christmas Common equipment so I manned the Cowley end while the other two lads went to top up the batteries and then we would check the circuits to Cowley. It was about a 25minute drive from Cowley so after a very long wait at the Cowley radio room they finally called me, apart from the maintenance checks it also turned out the Brakespears ales at the Fox also needed to be checked out.

Mike