Battery Charger

[Milesp99]

Hi,

My less than 2 year old Bosch battery is no longer holding a charge. I can jumpstart it easily and if I drive it for an hour or so it will hold enough charge to start the car if I stop for short periods of time but if left overnight won't start in the morning.

Battery under warranty but company (Tayna) is saying just needs an overnight charge.

Not sure that's likely in my experience but happy (ish) to try.

So - any recommendations for a battery charger - car is 3.0L - most of the ones I see in Halfords etc are suitable up to 2.0L - surely charging a battery is charging a battery?

Grateful for any recommendations!

[paintman]

Milesp99 said:

Hi,

My less than 2 year old Bosch battery is no longer holding a charge. I can jumpstart it easily and if I drive it for an hour or so it will hold enough charge to start the car if I stop for short periods of time but if left overnight won't start in the morning.

Battery under warranty but company (Tayna) is saying just needs an overnight charge.

Not sure that's likely in my experience but happy (ish) to try.

Won't do much for your battery OR your alternator.
https://www.optimabatteries.com/en-us/experience/2...

Why did your battery go flat in the first place?
Do you have a parasitic battery drain? Worth checking for.

Milesp99 said:

So - any recommendations for a battery charger - car is 3.0L - most of the ones I see in Halfords etc are suitable up to 2.0L - surely charging a battery is charging a battery?

Grateful for any recommendations!

Can't make any suggestions re current battery chargers, the one I've got is at least 30 years old & doesn't have an 'up to' rating marked on it.

[bluezedd]

Get yourself a CTEK MXS 5.0 and charge it up using the recondition mode and see how you get on. It is possible you do have a drain on your car though and might not solve the problem.

Imo a battery charger like the above is a must for me.

there was a cheaper charger too that someone mentioned on here that I quite liked the look of, and considered buying it as a second charger. Can't mind the brand though.

agree with charging the battery and then testing the alternator and also checking if there's something draining it.

EDIT: the brand is NOCO.

Edited by bluezedd on Sunday 29th March 16:08

[dhutch]

Bigger batteries need bigger chargers, however Halfords 'upto 2ltr' charger is a 5amp charger and should be fine, just might take 20hrs not 15. They also stock the Noco ones.

The CTEK units are nice, but also three times the price, which unless your using it regularly or leaving it on float is a lot of money. Can you not borrow one?

Daniel

[BrownBottle]

I bought one of these to charge my 5 series battery

https://www.amazon.co.uk/dp/B07T6GV32V/ref=cm_sw_r...

Tried starting it today to keep things moving as I hadn't driven it for about 4 weeks that's also when I removed the battery and charged it. Started first time and I could tell by the way it turned over the battery had plenty of juice.

[skywalker001]

Hi I found that sealey make really good chargers I use one of their schumacher range, would recommend

[finishing touch]

My old 3.2 CDI Merc has a (019) 95 amp hour battery.

This means that a 10amp charger would take 9.5 hours to charge it. (sort of) A 5amp would take 19 hours to do the same thing.


I like chargers with a gauge so you can tell at a glance how much it has charged / how long to go.
Had a Halfords one once (a present) that had a red LED that turned green. It got so I used to go and check it every half hour. Nope, still red.
Used to drive me mad so threw it in the bin and now I have this. see photo.

12 amps on high, 5 amps on low. £30 ish

From Merc 'won't turn over' to 'fires first time', 1.5 to 2 hours, and yes I do have a parasitic drain that I can't find.




p.s.
Just did a search. £32 from Argos

Edited by finishing touch on Saturday 25th April 08:06

[dhutch]

Yes,

All depends on the requirement obviously! That Argos one is a good high output charger, with an indicator, but also I expect otherwise very basic. If the aim is to get enough juice in to get it to crank, or to get it full quickly once or twice, it will do it just fine. Can't fault it, and will likely work well for the OP. It will get to 90% charge quicker than most others.

However you couldn't leave it on long term, more than 12-24 hours say, and I wouldn't want to use it regularly for even that long. IFOr that you would want a multi-stage electronically controlled charger such as the CTEX (or NOCO) range, which has a 8 stage charge and would likely get to 100% as fast (if the Argos one can even get to 100% SOC) even with half the max input power, but also be safe to leave on long term.

That said, I suspect the OP's battery is toast, due to an issue with the battery, or the usage profile of the vehicle. So you could also just borrow one once!


Daniel

[finishing touch]

dhutch said:

However you couldn't leave it on long term, more than 12-24 hours say, and I wouldn't want to use it regularly for even that long

Daniel

I think your missing the point Daniel of using a high output charger.
24 hours at 12 amps is 288 amp hours. That would charge my 3.2 litre Merc battery three times over from absolute flat. ( In theory )

The reason I favour a decent output charger is that after the car failing to start I want it to be running again asap. A couple or three hours at most.


I also don't have a problem with switching stuff off.
I turn off the lathe or the welder in the workshop, turn off the lights, lock the doors. I even turn off the oven when my pie is cooked, or whatever.
When I get to the stage of being senile then I won't have a car anyway. ( Or a gas cooker.)

Paul G

[dhutch]

finishing touch said:

I think your missing the point Daniel of using a high output charger.
24 hours at 12 amps is 288 amp hours. That would charge my 3.2 litre Merc battery three times over from absolute flat. ( In theory )

Not at all, I'm just drawing attention to the shortfalls of a more basic charger. Yes it will out the juice in faster for the first few hours, enough to get a start, but that's about it. The theory you mentioned doesn't hold up because all chargers will reduce the charge rather as the state of charge increases.
A digital multi stage charger will have a bulk constant-current stage, followed by a constant voltage stage, and on to various maintaining stages. A basic charger will be current and voltage limited (they are basically just a 14v transformer) and do a sort of reasonable job at smushing the two key stages into one, but will typically be at half their output by the time the reached any reasonable state of charge.

If what you want is quick turnaround from a supprise flat battery, you want an old battery, jump pack or booster box that will start a flat car instantly.

Daniel