Suzuki Swift - Trickle charging a battery

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Wed 15 Apr 2020 07:05
Suzuki Swift - Trickle charging a battery - Halmerend
Obviously, this post is related to my earlier one. I borrowed my neighbours Optimate battery charger but am struggling to get it attached directly onto the battery terminals. If I attach it to the terminal connectors will it still charge ok? Did this last night and it’s still charging this morning.
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Wed 15 Apr 2020 07:11
Suzuki Swift - Trickle charging a battery - jc2

You,ve answered your own question!

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Wed 15 Apr 2020 07:20
Suzuki Swift - Trickle charging a battery - Halmerend
Ha ha sorry :). It does sound daft.

I meant that if the orange charging light is showing, is that confirmation that it’s definitely charging? Or could the light just stay on for days because it’s not actually charging!
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Wed 15 Apr 2020 07:32
Suzuki Swift - Trickle charging a battery - elekie&a/c doctor
May be a good idea to get yourself a digital multimeter . At least you can verify any voltage increase with the charger connected . Pick one up from around £10 .

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Wed 15 Apr 2020 07:59
Suzuki Swift - Trickle charging a battery - Halmerend
Thanks, having a look now.
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Wed 15 Apr 2020 08:14
Suzuki Swift - Trickle charging a battery - daveyjp

I gave my tale of woe from yesterday on another thread,

In short. Went to start car yesterday. Just a click. I have a multimeter and battery was about 11v. I have a charger with a voltage readout and over a few hours it charged to 12.1v, the amber light was still on. This was enough to start the car and a good high speed run topped it to just over 12.5v

Info suggests the charger takes 15 hours to charge from very low on high charge and it will only show green at 12.4v.

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Wed 15 Apr 2020 10:04
Suzuki Swift - Trickle charging a battery - Will deBeast

Voltage readings when a battery has just been charging/discharging will only give a very rough idea of what's going on. The battery needs to 'rest' for a little while - say an hour.

A flat battery may show 11v. If I put a charger on it for an hour, and then remove the charger, it may show 12.2v or so. But just leave it for an hour, and it might be back to 11.5v.

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Wed 15 Apr 2020 09:59
Suzuki Swift - Trickle charging a battery - Will deBeast

A typical battery holds about 60Ah.

From completely* flat, at an average charge rate of 2A, you'd expect it to take about 30 hours to charge to full.

* very unlikely that it's completely flat, but just keeps the figures simple.

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Wed 15 Apr 2020 10:25
Suzuki Swift - Trickle charging a battery - Simon

An Optimate will take ages to charge a car battery. Just leave it to it and let it do its own process.

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Wed 15 Apr 2020 10:34
Suzuki Swift - Trickle charging a battery - Halmerend
Yes it’s only 0.6A. Been on for 15 hours and still showing orange. Car did start ok before I put it on too.
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Wed 15 Apr 2020 13:51
Suzuki Swift - Trickle charging a battery - daveyjp

If the car starts I would go and give it a run like I did yesterday, about 20 miles at up to 70mph.

I was wondering if my battery would be on the way out, but it started first turn this morning.

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