[Closed] Car batteries...

A charger is a handy thing to have, in general.

We've just been through this and having had to jump start the second car a couple of times we've taken the plunge.

Gone for the CTEK MXS 5.0 which will condition the battery, then monitor and trickle charge at 0.8A. The 12V accessory sockets are permanently live in our cat as well so we got the plug in for that. Hopefully the lead trailing across the driver's seat will reduce the chance of the wife driving off with the charger still attached.

Looks like a good option, and Amazon reviews seem to indicate it’ll help me from accidentally frying my Beemers traditionally delicate setup.  Our Kuga should be simple.

Had to use my car instead of the bosses yesterday because of a flat battery so it's now charged up waiting to go back in. Might actually take both out, link them together and stick the caravan solar panel onto them to keep them topped up.
Aldi do a smart charger from time to time which gets decent reviews but I've no personal experience of them. 3 year warranty though as with most of their stuff.

I like my in-laws Optimate 4 trickle charger/battery conditioner, but as my car is in the street* I was wondering about a booster unit, as it runs fine once started. Anyone got a recommendation for one if those?

*cant run wires to it & don’t want to leave it unlocked with the battery charging in the house

I've seen pole where the base sits under the wheel and people use these to run cables overhead of the footway to supply caravans and the like. Might work depending on how busy your street is.

Timely thread. I'm in a similar situation. Car currently gets uses for two journeys a week on Wednesday. My wife driving to work at a school, circa 10 mile round trip, and the weekly trip to the supermarket, circa 5 miles.

We don't have a drive or garage so was wondering if those solar battery chargers are any good. Seen one in Halfords that's 12v, 6w, so that works out at 0.5A. Does anyone have experience of using them at all?

you need to check whether you have a lithium ion battery, as quite a few bmws (and I presume other makes too) that have the stop/start functionality use a lithium ion battery as opposed to a traditional lead acid or AGM (my M4 has a lithium ion battery). And if it does use a lithium ion battery, you need to use a charger that is compatible with lithium ion batteries, not all are compatible.

If you use a non lithium ion charger with a lithium ion battery you will damage the battery , and lithium ion batteries are exceptionally expensive to replace -- I think the one in my BMW is around £1k.

I thought a solar one might be a good idea, especially with the live accessory sockets but really struggled to find out about internal protection with them and found comments about damaged batteries. Perhaps I didn't look hard enough.

As per the other car battery thread, I've just got a NOCO Genius charger and it has a Lithium battery setting.

I think that the solar panels only delay the inevitable, the smaller ones won't keep up with the normal rate of discharge due to alarms, ecu standby etc. in modern cars. I've used them for years on motorbike and caravan batteries but never did any measurement or comparison so can't say if it was worth it or not. 2005 Suzuki still had its original battery when I sold it last year though, still working fine.
I've got both car batteries hooked up to one now though and a volt meter connected so I'll keep an eye on them and see what occurs.

I got one of the Aldi ones a while ago

When it worked it was really good - not just for the price - really good

However its stopper working and so far the customer service has been rubbish in terms of trying to get a replacement or repair - I'll update this as and when I have any better news

Both our cars have now died. I've ordered a charger and planning to remove and charge the batteries. I've disconnected the battery in the bigger car too as we just use the little one

I've been using my motorbike battery charger (optimiser 3x) which can do car batteries as well. Car was more or less dead a couple of days ago. It takes a long time on a car battery but it's brought it back to life.

jeffl
Subscriber
We don’t have a drive or garage so was wondering if those solar battery chargers are any good. Seen one in Halfords that’s 12v, 6w, so that works out at 0.5A. Does anyone have experience of using them at all?

I've been looking into those, I have a couple of questions too.

1 Is 12v enough to actually keep the battery topped up, I vaguely recall that car batteries need 13.something volts to charge.

2 Is there any danger of these things overcharging the battery? I can't find any reference to overcharge protection in any of the listings

Same situation here, for the past few weeks, one car has done about 15 miles last week going to Sainsburys and back, the other did about 2 miles, once or twice, going to the local shop for a mid week milk & bread top up shop.

About a million years ago I bought the cheapest trickle charger Halfords sold. It's been worth its weight in gold.

Mind you, I've only ever owned cars with cheap old boring lead acid batteries, that don't spontaneously combust when you use an external charger.

1 Is 12v enough to actually keep the battery topped up, I vaguely recall that car batteries need 13.something volts to charge.

2 Is there any danger of these things overcharging the battery? I can’t find any reference to overcharge protection in any of the listings

1) I think what they mean is "works on a 12V battery". I wouldn't trust the public to translate "14.8V output" into "works on my car's 12V battery".

2) no

mrmonkfinger
Member
1) I think what they mean is “works on a 12V battery”. I wouldn’t trust the public to translate “14.8V output” into “works on my car’s 12V battery”.

2) no

Cool thanks.

Today's challenge children is to write a post with the words 'lithium ion battery' more times in it than Julians managed. Peanut to the winner... 😊

Today’s challenge children is to write a post with the words ‘lithium ion battery’ more times in it than Juians managed. Peanut to the winner… 😊

whoops 🙂

As per the other car battery thread, I’ve just got a NOCO Genius charger and it has a Lithium battery setting.

I've got on of these as I frequently go weeks at a time between using the car anyway and the C-Maxerati battery doesn't like being left idle for some reason.

Already paid for itself by resurrecting a totally dead spare battery. So dead that even the NOCO repair mode wouldn't recognize it. But you can put it in 13.6V PSU mode and it just pumps 5A into the battery for a few days until acid is fizzing out the top, then you can put it in repair mode. Wouldn't trust that battery in a car but it's great for running 12V stuff in the workshop and jump starting.

Reminds me, I need to make up some extension cables for it so I can reach the cars on the driveway, and I'm not paying NOCO prices for them!

Reminds me, I need to make up some extension cables for it so I can reach the cars on the driveway, and I’m not paying NOCO prices for them!

Have you not got a 'normal' extension lead/reel? That's all I used; extension reel out to car, excess cable wound off it and slung under the car (I figured it might get a bit too warm if it's wound around the reel, connected, for 48+ hours), charger connected, bucket over charger and reel, just in case it rained (which it didn't)

Harrys garage on yt covered this on the wintering of his cars. He went for the ctec. He is sponsored by them but does explain why they are better.

In fact if u start watching harrys garage don't plan on doing much else for the rest of the day, week...its compulsive viewing.

He s got some other tips for laying up cars, excess tyre pressure, battery, Windows open if poss, handbrake off, fuel tank brimmed.

Thanks Julians.    I had an extensive search to see if my BM has a Lithium battery.  Not easy as its under, well... lots.  But various sites seem to indicate its AGM (320d touring F31 April 2017).

Anyhow the NOCO 2 is cheaper then the CTEK albeit maybe a bit slower so I've changed my order for that just in case, as its handy to have AGM/Lithium options for the future.

I noticed the NOCO needs you to switch it between Lithium and lead acid - does anyone know if it'll auto switch if theres a mistake?

Another thanks for the reminder, mine hasn't been driven since 18th March so just put the caravan solar panel on it. Cheers

does anyone know if it’ll auto switch if theres a mistake?

Don't think so, from memory the instructions say "be dead sure you're charging a lithium battery before selecting lithium mode" and it takes a conscious long-press of the mode selector button to so you can't accidentally select it. Suggests that bit at least isn't 'smart'

I noticed the NOCO needs you to switch it between Lithium and lead acid – does anyone know if it’ll auto switch if theres a mistake?

No it won't, you have to put it into lithium mode. It does remember what mode it was last in though, so you don't have to set it to that mode every time.

As an aside I bought a noco genius (3200 I think) and its a nice bit of kit, good value.

boblo
Member

Today’s challenge children is to write a post with the words ‘lithium ion battery’ more times in it than Julians managed. Peanut to the winner… 😊

I think as he has a ‘lithium ion battery’ he's trying to remind himself because he has a ‘lithium ion battery’ not to connect a charger that would harm a ‘lithium ion battery’.
As many BMW's have a ‘lithium ion battery’ standard chargers won't properly charge a ‘lithium ion battery’ or even damage a ‘lithium ion battery’.
The expense of replacing a ‘lithium ion battery’ is quite shocking which leads me to think is a ‘lithium ion battery’ the best solution to a cars electrics given a ‘lithium ion battery’ can be damaged quite easily by not knowing the car has a ‘lithium ion battery’, and connecting a charger not suitable for a ‘lithium ion battery’ the world is full of traps but one you probably didn't know was charging a ‘lithium ion battery’ with a non ‘lithium ion battery’ compatible charger could damage your ‘lithium ion battery’.
So in somethingion if you have a ‘lithium ion battery’ or suspect you have a ‘lithium ion battery’ in your car please consult with an expert on what charger to use for your ‘lithium ion battery’ or you could be buying a new ‘lithium ion battery’ and as we now know a ‘lithium ion battery’ is a very expensive thing. Just how many people knew there was so much to know about a ‘lithium ion battery’.

Childish I know

Well, typing my number plate in Halfords or Eurocarparts reveals an AGM battery every time...

Damn you Mr Overshoot, damn you. PM me your address and I'll get your 'prize' in the post forthwith. You're lucky, Mrs Boblo was hoovering under the settee cushions and, errrm, 'came across' your prize. Lucky you 😉

Are any of the trickle chargers fine to run with outside? I have a garage but it's full of crap (mostly bike related) so I can't actually park my car in it. Can you run a trickle charger with the bonnet down and the power lead just run into the garage (and from there I can use an extension to connect it to the wall socket which is inconveniently at the far end of the garage).

Or am I better off just getting a standard charger and using it every week or so (for a couple of hours each time when the forecast is good...)? If the latter are there any recommended models?

I believe the CTEK are IP rated. However, I just ordered the 2.5 extension for the low voltage side. The charger lives in the garage and the battery connection under the bonnet. Nothing exposed.

From my previous post:

extension reel out to car, excess cable wound off it and slung under the car (I figured it might get a bit too warm if it’s wound around the reel, connected, for 48+ hours), charger connected, bucket over charger and reel, just in case it rained (which it didn’t)

I run an extension lead out to the car, there's a handy 'shelf' under the bonnet (fuse box/air filter) that's just the right size to put it on.

extension reel out to car, excess cable wound off it and slung under the car (I figured it might get a bit too warm if it’s wound around the reel, connected, for 48+ hours), charger connected, bucket over charger and reel, just in case it rained (which it didn’t)

Running a 2500W chainsaw maybe, a few mA into a charger is probably less than the solar gain!

Another dead car here. Removed battery from 10 year old focus and it appears to be the original. I've had it on an ancient Halfords trickle charger so I'll see if it's done the job later.

Are any of the trickle chargers fine to run with outside? I have a garage but it’s full of crap (mostly bike related) so I can’t actually park my car in it. Can you run a trickle charger with the bonnet down and the power lead just run into the garage (and from there I can use an extension to connect it to the wall socket which is inconveniently at the far end of the garage).

I kind of do it the other way round - my Mk2 sits at the side of the house, the CTEK lives inside on the side-window sill and connects to the battery via an extension leads on the 12v side of things and a permanently fixed compatible socket on the battery. The lead is happy enough with the window shut over it, the join between lead and car is under the bonnet.

It's not quite that simple: I ended up using a long Optimate lead and battery connection because I had one already, and a converter so it was compatible with the CTEX's bespoke socket. All works fine and there are no open connections to get wet plus the charger is safely inside along with any mains electrical cables.

My NOCO Genius 2 arrived Saturday.  The car showed <25% and charged to 75% during the course of yesterday.  I was dismayed to find it at 25% again this morning.

It never reached the full/conditioning phase so it maybe because its - I think - the original and therefore 12 years old...

Running a 2500W chainsaw maybe, a few mA into a charger is probably less than the solar gain!

Yeah, fair enough, I just figured better safe than sorry.

The car showed <25% and charged to 75% during the course of yesterday. I was dismayed to find it at 25% again this morning.

Mine showed weird readings for a while (using a Noco), especially when I took the charger off then put it on again. I just left it there to do what it was doing. Took a good 48hours to get fully charged up from pancake flat.

I used my car for the first time for 9 days today and got a low battery charge warning on the dash. It's a 2010 5 series touring, anyone know where the battery is?

Also, my 12v sockets only stay live for about 15 minutes at a time, I assume this means I'll need to connect any sort of charger directly to the battery?

It’s a 2010 5 series touring, anyone know where the battery is?

I think they put the battery under the boot floor on the F11, the E61's was behind the trim on the RH side of the luggage compartment. You can connect a charger to the terminals under the bonnet rather than having to root around in the boot.

Any idea if new car batteries come fully charged when purchased, what the shelf life is, and how quickly they discharge if unconnected?

My car was flashing up 'low battery charge' errors a few months ago (pre lockdown). Original battery in a 7 year old car with 145k miles.
I bought a fancy pants Bosch battery about 6 weeks ago but haven't fitted it yet. I've been using the car once a week for a 30 minute round trip with the original battery, still starts ok and the low battery has only come on once in the last 4 weeks.

Is it worth putting the new battery in now, or save it until later?

any idea how long one should run a vehicle to re-charge what's used up in ignition, and then add juice to the battery while on idle?

mine was unhappy starting 10 days ago when i needed to do a big-shop, but as I don't need to drive anywhere, any time soon (ebike + bike trailer FTW), I don't want to totally run the battery down, nor start it up and not replenish the battery 'cos i've turned it off too soon. 10-15 mins?

2011 VW diesel if it makes a difference...

any idea how long one should run a vehicle to re-charge what’s used up in ignition, and then add juice to the battery while on idle?

Genuinely, just buy a charger. They cost about £30 and running a car on idle to charge the battery is pretty bad, both in terms of "it's not very good for the car" and "you're spewing unnecessary crap into the air, especially with a ten year old diesel".

What IHN said.

You’re better buying a charger, I bought one from screwfix for less than £20.
Or jump start the car and drive it for an hour, keeping the revs up about 2k or so.

Hungry monkey

The AA are the only ones I found that covered this well.

We have a lot of company cars laid up whilst employees are on furlough and I know manyof them are on the street. I asked the fleet manager what to do for those employees and he pretty much said the below. I tested this with a diesel Qashqai before attaching the solar panel. 15 mins of idle/running with accelerator at about 1500 rpm for a lot of the time. This lifted the battery from 11.8v to 12.3v

https://www.theaa.com/driving-advice/laying-up

Battery maintenance – If you can, connect your car's battery to a mains-powered battery maintainer. If you can't, start the engine once a week and allow it to run for about 15 minutes. This will re-charge the battery and help keep the engine in good condition. It’s important to allow the engine to run for this long so the battery can charge properly. In the case of petrol engine cars, it also helps to prevent engines from flooding with fuel. Never leave your car unattended with the engine running

Some other good tips in the AA article including the fact that it is best to have a full tank of fuel to prevent condensation in the fuel tank

In the case of petrol engine cars, it also helps to prevent engines from flooding with fuel.

Feels a bit "auto choke carburettor", that bit of advice. An actual injection system from circa 1985 onward, should never flood anything. AFAIK.

Any views on whether you need to disconnect the battery from the car before charging it with a main charger? Up to the 1990s it wasn't a problem, but I'm not sure now - are you likely to upset the electronics more by disconnecting the battery or by connecting a smart charger?

Hmmm. I wish I’d paid the extra for the bigger one now.  Turns out my car has a 90AH battery, it’s going to take about 40rs to charge!

Where I live, everyone heads abroad for the summer for 6-8 weeks and many buy a new car battery - some every year.

My musings on a <£10 solar trickle charger go unheard - every year.

Expats....

(3 weeks you should be fine though)

boblo
Member

Damn you Mr Overshoot, damn you. PM me your address and I’ll get your ‘prize’ in the post forthwith. You’re lucky, Mrs Boblo was hoovering under the settee cushions and, errrm, ‘came across’ your prize. Lucky you 😉

Don't worry boblo I've been at work almost every bloody day since the "lockdown light" started so my battery is fine.