Battery maintenance

Discuss Electrical problems here.
Forum rules
By using this site, you agree to our rules. Please see: Terms of Use
Post Reply
les
Minor Maniac
Posts: 9011
Joined: Tue Feb 12, 2002 12:00 am
Location: kent
MMOC Member: Yes

Battery maintenance

Post by les »

I’ve removed the battery from my van, I can’t see me using it until the spring. I have it on charge using an Accumate charger, it now indicates charged, however it can be left connected but I’m not inclined to do this. I would like to know the correct way to maintain the battery over a period of time, for example: When charged, disconnect leave, and maybe connect again in a week or so ? Disconnect and discharge for a while with a 12 v bulb, then after a day or so charge again ? Or indeed some other method to maintain a healthy battery. Thank you.

philthehill
Minor Maniac
Posts: 11303
Joined: Thu Jul 19, 2012 12:05 pm
Location: Hampshire
MMOC Member: Yes

Re: Battery maintenance

Post by philthehill »

The Accumate charger can be left connected and charging without any concerns.

The battery will run down and the Accumate charger will determine when to start charging the battery again.
The Accumate takes on board the problem of determining whether to charge or not so you always have charged battery.
The only maintenance required is maintaining the electrolyte at the right level.
I have had a Accumate charger 12V/6V for several years and I have never had any concerns about leaving the battery connected to the charger over a period of time.
I also know several people who have used Accumate chargers again without concerns.

So Les to answer your question I would recommend that you disconnect but not remove the battery and keep the Accumate charger connected throughout the winter whilst keeping an eye on the electrolyte levels. Keep the terminals covered with battery terminal acid/corrosion neutralising grease.
https://www.ebay.co.uk/itm/351459590489 ... BMrpiykO9k

les
Minor Maniac
Posts: 9011
Joined: Tue Feb 12, 2002 12:00 am
Location: kent
MMOC Member: Yes

Re: Battery maintenance

Post by les »

Thanks Phil, yes agreed the charger is designed for being left connected, I’ll just have to overcome my distrust of leaving stuff running unattended for long periods. The battery is sealed.
Just one more thing ——-( I sound like Columbo saying that !) ——-can I expect the green light to go out and the charging (orange) lamp to light when the charge drops and when again charged see the green lamp again. Or once charged, would the green lamp stay alight all the time the charger is connected. Sorry to be pedantic over this but I’m interested.
Last edited by les on Fri Nov 29, 2024 10:39 pm, edited 1 time in total.

User avatar
svenedin
Minor Legend
Posts: 2193
Joined: Fri Aug 29, 2014 9:27 am
Location: Surrey
MMOC Member: Yes

Re: Battery maintenance

Post by svenedin »

I have a CTEK MX5.0 battery charger which also has an automatic battery maintenance function. It cannot overcharge the battery and it is perfectly safe to leave it connected for weeks or months (indeed I have done so with no issues). I do have a battery isolator (a simple thumbwheel connected to the terminal post) so I isolate the battery from the car before leaving the battery on charge.

I can understand your reticence to leaving a battery connected to a charger. Years ago I would take the battery out of the car to charge it (sometimes spilling acid on my clothes and burning holes). I would then nervously leave the battery charging worrying that I would "boil" it. There is no fear of this with a good quality modern charger.

Car batteries are easily ruined by leaving them in a discharged state and there is no going back from that so it is better to leave them on a maintenance charger.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
les
Minor Maniac
Posts: 9011
Joined: Tue Feb 12, 2002 12:00 am
Location: kent
MMOC Member: Yes

Re: Battery maintenance

Post by les »

Thanks Stephen, yes it’s just a case overcoming my inhibitions regarding this. I have added to my response to Phil’s reply with a further query.

Peted7202
Minor Fan
Posts: 194
Joined: Tue May 31, 2022 2:44 pm
MMOC Member: Yes

Re: Battery maintenance

Post by Peted7202 »

I have a MGA. An Optimate charger is fitted every time it is not being used and is always in the garage. From October to April it is not driven and it is attached permanently.
User avatar
geoberni
Minor Legend
Posts: 4005
Joined: Fri Aug 04, 2017 11:19 am
Location: North Leicestershire
MMOC Member: Yes

Re: Battery maintenance

Post by geoberni »

I don't have a fancy modern charger, but I do know that (cheap fake ebay stuff excepted) they are designed to sense the discharge and top the battery up again as required.
If you look online you'll find that the MGOC, which has quite a good shop in it's portfolio, sells the Accumate charger.
https://www.mgocspares.co.uk/parts/1_3_ ... nditioners

A lead acid type battery, including all the modern variations with the different additives in them, will be harmed if it drops below around 11.5 volts, which is basically down to 10% charge. 12v is viewed as 50% charged.
My car's battery isn't isolated, because I have a tracker fitted which needs the power, so I have a minuscule drain on the battery all the time.
I check it every week(ish) and it takes around 7-8 weeks to drop to near 12v, that's the lowest I'll ever let it get before putting the Charger on it for a day.
(Preferably a sunny day when the Solar Panels are providing free power anyway :lol: )

You'll be fine with the Accumate left connected, that's it's "raison d'etre" :)
Basil the 1955 series II

Image
les
Minor Maniac
Posts: 9011
Joined: Tue Feb 12, 2002 12:00 am
Location: kent
MMOC Member: Yes

Re: Battery maintenance

Post by les »

Thanks to all, yes I need to get a grip, man !! :D

User avatar
rocco
Minor Fan
Posts: 343
Joined: Fri Jul 15, 2022 8:59 pm
Location: Germany
MMOC Member: No

Re: Battery maintenance

Post by rocco »

I've just removed my battery today and stuck it on the charger at 2A. It took quite a hammering today getting the engine started. I have a tester that shows me it's at 70% so I'll leave to slowly charge up for a few hours and then I'll disconnect it and leave it indoors over winter. I can always stick it back on the charger next year if the rating drops drastically.

Just looking at the negative cable, it looks a bit frayed. Is it worth replacing it or is fine as it is?
signal-2024-11-30-144358_002.jpeg
signal-2024-11-30-144358_002.jpeg (431.54 KiB) Viewed 1364 times
1961 Morris Minor 948
1970 Morris Minor 1098
User avatar
geoberni
Minor Legend
Posts: 4005
Joined: Fri Aug 04, 2017 11:19 am
Location: North Leicestershire
MMOC Member: Yes

Re: Battery maintenance

Post by geoberni »

rocco wrote: Sat Nov 30, 2024 1:46 pm

Just looking at the negative cable, it looks a bit frayed. Is it worth replacing it or is fine as it is?
I've seen a lot worse still working, though the connection to the body looks like it might need cleaning.
What you could do (and how you do it depends on whether you're a key start) is clean it and connect it all up, put a multi-meter on Volts across that lead, from battery post to the retaining bolt, and crank the engine over for a few seconds with no Ign on.
If the Voltage drop across that earth strap is more than 0.5 volt I'd replace it.

See this old post of mine from a couple of years ago when I had a frayed cable. :roll:
viewtopic.php?p=680985#p680985
Basil the 1955 series II

Image
User avatar
Mr Spigot
Minor Fan
Posts: 231
Joined: Mon Sep 13, 2021 2:44 pm
Location: East Sussex
MMOC Member: Yes

Re: Battery maintenance

Post by Mr Spigot »

A very useful and informative series of posts. I have a couple of questions:

1. I have a Clarke CC80 charger which seems to work well, but I am not sure if it can safely be left permanently left on while the car is over-wintered. Would an Accumate charger (or any other make) be any better?

2. Is Liqui Moly - Battery Post Grease any better than Vaseline for terminals?

Thanks.
1960 2 door with 1275 Midget engine - WOI 577 - owned since 1990
1952 MM convertible with original engine - MWD 305 - owned since 2023
User avatar
svenedin
Minor Legend
Posts: 2193
Joined: Fri Aug 29, 2014 9:27 am
Location: Surrey
MMOC Member: Yes

Re: Battery maintenance

Post by svenedin »

Mr Spigot wrote: Fri Dec 06, 2024 12:03 pm A very useful and informative series of posts. I have a couple of questions:

1. I have a Clarke CC80 charger which seems to work well, but I am not sure if it can safely be left permanently left on while the car is over-wintered. Would an Accumate charger (or any other make) be any better?

2. Is Liqui Moly - Battery Post Grease any better than Vaseline for terminals?

Thanks.
The instruction for the Clarke CC80 are here:https://www.clarkeservice.co.uk/manuals ... r_Rev3.pdf

The instructions say "Disconnect the charger when charging is complete otherwise damage to the battery could occur should the charger be left connected for a prolonged period". Therefore, this charger is not designed for prolonged maintenance charging.

The CTEK MX5.0 that I use is specifically designed for prolonged connection. It is also much smaller than old fashioned chargers.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
User avatar
Chief
Minor Addict
Posts: 696
Joined: Thu Apr 15, 2004 11:29 pm
Location: Lincs.
MMOC Member: Yes

Re: Battery maintenance

Post by Chief »

svenedin wrote: Fri Dec 06, 2024 12:50 pm The CTEK MX5.0 that I use is specifically designed for prolonged connection. It is also much smaller than old fashioned chargers.
Would that actually be the Ctek MXS 5.0?

I have to admit while not used for the over-wintering long term charge, it (MXS) is a good little charger :) (it must be good since I've seen Rolls Royce badged versions in show rooms).
oliver90owner
Minor Legend
Posts: 1768
Joined: Thu May 12, 2016 6:33 am
MMOC Member: No

Re: Battery maintenance

Post by oliver90owner »

Chief wrote: Fri Dec 06, 2024 3:13 pm
svenedin wrote: Fri Dec 06, 2024 12:50 pm The CTEK MX5.0 that I use is specifically designed for prolonged connection. It is also much smaller than old fashioned chargers.
Would that actually be the Ctek MXS 5.0?

I have to admit while not used for the over-wintering long term charge, it (MXS) is a good little charger :) (it must be good since I've seen Rolls Royce badged versions in show rooms).
Yes. CTEK advise that the reconditioning cycle is only used once per year and after deep discharge. These CTEK chargers (the 5.0 and the more powerful option) are favoured by farmers. That is always a good indication, as farmers don’t usually spend money on items that don’t do what is expected of them.

I first borrowed one from a friend (an agricultural machinery dealer) and made my purchase soon afterwards.
User avatar
svenedin
Minor Legend
Posts: 2193
Joined: Fri Aug 29, 2014 9:27 am
Location: Surrey
MMOC Member: Yes

Re: Battery maintenance

Post by svenedin »

Chief wrote: Fri Dec 06, 2024 3:13 pm
svenedin wrote: Fri Dec 06, 2024 12:50 pm The CTEK MX5.0 that I use is specifically designed for prolonged connection. It is also much smaller than old fashioned chargers.
Would that actually be the Ctek MXS 5.0?

I have to admit while not used for the over-wintering long term charge, it (MXS) is a good little charger :) (it must be good since I've seen Rolls Royce badged versions in show rooms).
Yes the Ctek MXS 5.0.

I really like it. It comes with standard crocodile type clips but you can also buy a connector that you permanently connect to the battery. Then when you need to charge the battery the charger just connects with a simple connector rather than crocodile clips. I use that with my modern Audi as the bonnet will not close with crocodile clips attached to the battery. Not an issue with the Morris.

https://www.ctek.com/uk/battery-charger ... -eyelet-m8

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
User avatar
Chief
Minor Addict
Posts: 696
Joined: Thu Apr 15, 2004 11:29 pm
Location: Lincs.
MMOC Member: Yes

Re: Battery maintenance

Post by Chief »

My only complaint about ours is the way all three leads somehow turn to christmas lights and tangle themselves up when not in use :D

I never realised the eyelet cable that also comes with it was for that purpose, I always thought it was for some form of motorcycle battery.
woodypup59
Newbie
Posts: 4
Joined: Wed Nov 13, 2024 8:33 am
Location: Herts
MMOC Member: No

Re: Battery maintenance

Post by woodypup59 »

I always use batteries with cell caps so I can monitor water levels.

I reckon leaving the smart charger connected permanently "boil" water off more than when not connected.

So I charge every fortnight, leaving the charger on until the lights say its full - probably a day or so.
oliver90owner
Minor Legend
Posts: 1768
Joined: Thu May 12, 2016 6:33 am
MMOC Member: No

Re: Battery maintenance

Post by oliver90owner »

woodypup59 wrote: Sat Dec 07, 2024 8:10 am I always use batteries with cell caps so I can monitor water levels.

I reckon leaving the smart charger connected permanently "boil" water off more than when not connected.

So I charge every fortnight, leaving the charger on until the lights say its full - probably a day or so.
As long as the battery voltage is maintained at no higher than 14.4V, no electrolysis of the electrolyte will occur - until one cell drops voltage , meaning the other five then can get an overcharge voltage.

The only real advantage with capped, open-cell, flooded lead acid batteries is that the battery cells can be occasionally balanced by charging to the point of electrolysis occurring on all cells - and subsequently requiring topping up with distilled water.

Typically, the modern automotive battery has such thin plates that overcharging is quite likely to involve loss of plate material to the bottom of the cells.
alanworland
Minor Legend
Posts: 1450
Joined: Tue Jan 30, 2007 10:09 pm
Location: Essex
MMOC Member: No

Re: Battery maintenance

Post by alanworland »

Don't think my maintenance charger is made by Halfords anymore but has been in use and 'on' for at least 20 years doing it's job admirably!

Alan
Image
Post Reply