Girly question re battery chargers...

Flyboy152

birkee wrote: »

No "Where on earth" about it.
I have a charger which will only work if it recognises a battery is connected. A flat battery is a 'brick'. (I do have two chargers)

Second point is, that it is better to maintain the onboard battery, than to overcome it with a jump starter. Are you going to use the jump starter all day, as you go about your business doing short runs?

Third point, is that short runs are battery killers. Back when dynamos were common, it was reckoned by experts, that the charge removed when starting the car, took 20 miles driving to replace.

Fourth point is, that a lead acid battery that has gone below 10.5 volts, will become irrecoverable fairly quickly. (days) A FLAT battery is a 'deal with it NOW' problem.

My authority on batteries?
Several years working in a battery testing laboratory evaluating all their characteristics.

I don't think you "authority" gave you much of an insight on how battery jump packs work.

P.S. How do you maintain a maintenance free battery?

shaun_from_Africa

Flyboy152 wrote: »

P.S. How do you maintain a maintenance free battery?

By ensuring that it is kept as fully charged as possible and making sure that the battery terminals, connectors and leads are kept corrosion free, clean and tight.

hucknallglynnbob

pinkteapot wrote: »

After an incident last winter where our car battery died in that really cold weather (luckily we had Green Flag cover including Homestart), we're thinking about getting one of those car battery charger things from Halfords.

How easy are they to use? How do the attach to the car battery? Do you have to disassemble anything under the bonnet to use them?

My car maintenance knowledge is limited to checking the oil, filling the screenwash and checking the tyre pressure. :rotfl:

without wanting to sound pedantic go to your local car spares/halfords get your battery checked if you need a new one they arent that expensive and it will save you calling out green flag etc and will most probably last you 4-5 years cant see the point messing about with jump leads chargers etc.

Gloomendoom

Following on from the debate on whether or not it is possible to recharge a very heavily discharged battery. It seems there is a way to fool a charger into charging a 'bricked' battery...

How To Charge an AGM Battery - A Current Affair - How To Do It

Read more: http://www.hotrod.com/techarticles/general/hrdp_1009_how_to_charge_a_agm_battery/viewall.html#ixzz1f2dtzOCA

pinkteapot

Resurrecting this thread with good reason.

Kicking myself as after all the good advice I failed to change the battery or buy a charger/jump-starter. The battery was behaving. Until this morning, when I went to start the car and there was nothing. A brief glimmer from the dashboard lights and that was it. On Tuesday I said it was sluggish to start and we needed to do a long run this weekend, but we haven't had a chance before today.

It's booked in for a battery change on Monday (the garage will check it's just a battery problem - assume it is). We'll jump it to get it to the garage. The comments above re dealing with flat batteries quickly have worried me though. What could happen? We can't get to a shop to get a charger/jump-starter until Sunday due to work etc.

If it's just that leaving it a couple of days will completely break the battery then it's not the end of the world as if it won't jump Sunday/Monday I can call Green Flag and have the car moved to the garage for free. But is there a chance it could cause any other damage to the car in the meantime?

Next time, I'll listen to you.

pendulum

No damage to car, but you may need to re-enter the radio code, and it may run a bit strangely for a few miles as the computer relearns all its various sensor settings.

pinkteapot

Cool, thanks, will get it going again as soon as we can.

forgotmyname

It might lose its ECU settings, Radio code and Window sensors.

Instructions will be in the handbook or FREEly available online dont buy the secrets off ebay etc.

It might take a couple of miles of driving for the ECU to relearn its settings, But it may actually run better
if it does that.

pinkteapot

Well.... That was pointless.

Got a jump-start kit, charged it up overnight as per the instructions. Tried to jump the car and... Nothing.

Called out Green Flag who used their jump start kit and it started first time.

Since the car was actually running, I took it to the garage it's booked into on Monday and left it there. Green Flag guy tested the alternator which was fine and said the battery looked like the original and was probably just kn*ckered.

Trying to decide whether to take the jump kit back to Halfords and ask for a refund, or assume that I'm being rubbish and didn't do it right. Unfortunately I have no other dead cars to test it on.

forgotmyname

Cheap jumpstarters are rubbish, They dont put out enough power. Cheap leads,

I had a pair of chunky jump leads, Wire broke so i stripped it back to refix and found the copper core was only
about 2mm thick. Compared that to some cheaper leads i bought that had an 8mm core.