Numrous posts on battery problems and still no definitive answer!

The technical FAQ just says that some people on the board use CTEK chargers but for most people in the real world a garage with mains power is not a reality so the CTEK chargers are useless.

This leaves a lot of S2 drivers with the conundrum of keeping the battery charged when not using for longer than a week!

Admins ... the community need a definitive answer on this issue as it has caused a lot of grief to a lot of people!
Can you please look at the options below and add your expertise and experience so that S2 community can alleviate this headache?


To maintain the battery you have the following options:-

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[1] Disconnect the battery if you know you won't use the S for longer than a week.
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You lose the alarm (which is what is draining the battery) but when the would be thief connects it, the immobiliser will still to be activated so you should be safe on that score, but how would Insurance companies view that if the car was nicked.?

If you do this, What is the correct sequence for disconncting and then reconnecting?

Also, how long can an S2 OEM disconnected battery hold its charge before you start having problems with it. Will it still discharge and therefore be damaged? (I believe there can be an issue with alarm ECU being damaged if you allow the battery to discharge?)

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[2] Use a portable jump starter.
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something like this ...
http://www.toolstation.com/shop/p91757

Again, will allowing the battery to discharge damage the battery / alarm ECU?

Will this reduce the life/effectiveness of the battery?


PRESUMABLY BOTH OPTIONS ABOVE WOULD MEAN RE-ENTERING CODES ETC ONCE YOU WERE UP AND RUNNING AGAIN SO NOT THE BEST OTIONS

THE BEST OPTION LEFT SEEMS TO BE ...

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[3] Use a solar charger for a 12V lead acid battery
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1.5W CHARGERS ... (may all be the same charger)

http://www.amazon.co.uk/Sealey-SPP01-Solar..._pr_product_top

http://www.amazon.co.uk/Solar-Powered-1-5W..._pr_product_top

http://www.amazon.co.uk/Solar-Battery-Char..._pr_product_top

3W CHARGER

http://www.powerbee.co.uk/Solar-Panel-Kits...CFUUe4QodhWttXw

4W CHARGER

http://www.amazon.co.uk/Solar-Briefcase-Ba...ref=pd_sim_sg_4


There is a great deal of confusion as to the use of these chargers with the lighter socket in the S.

Some say they have used these solar chargers through the lighter socket in the S, but others say you can't do this as the lighter socket is not 'live' when the keys are out of ignition.

Does anyone know 100% that the S2000 lighter socket is not 'live' when keys are out of ignition?

If so that solar charger can only be used by feeding the cable out the door and over the wing into the the engine compartment (about 2 inches of wire showing) which is acceptable but not ideal.

It is possible to modify the lighter socket so that it is live with the keys out the ignition but it gets quite technical and awkward ....

"The only remedy is to make the lighter socket permanently 'live' by connecting it to the main battery. This can be done safely, but ensure that you fuse the positive wire with a fairly low amperage in-line fuse of not more than 5 amps, and the fuse should be as close to the positive battery terminal as possible. Make sure that you NEVER plug anything else into the lighter socket (especially the lighter itself, as that draws a high current).
Alternatively, run well insulated -ve & +ve cables direct from the battery (again with a 5A fuse near the battery) into the cabin, and connect to a 'female' plug of a good make ... cut off the rubbish croc-clips of the solar panel cable, and correctly wire up into the 'male' matching plug.When you want to use the solar charger, plug the connectors together"

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[4] disable the internal sensor
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Something that a lot of Elise owners do when parking their car in their garage is disable the internal microwave sensor, because it's that that really drains the battery. I don't know for certain that the Honda alarm has the same problem but it seems reasonable to suspect it. On the S, to disable the internal sensor, press the lock button again once you've locked up and set the alarm. The indicators will flash to confirm.

 

"Does anyone know 100% that the S2000 lighter socket is not 'live' when keys are out of ignition?"

Yes sir that is a fact.

 

Option 4

Go out to the car start it up and run the car for 20 minutes every month.

 

[QUOTE=gbduo,Dec 7 2010, 11:11 PM] Option 4

 

Be wary of solar chargers, I've been involved in a project this year that tested them and not many were capable of actually 'charging' a battery. In the end an $800 1m sq. Panel could only just begin to provide constant current to a vehicle battery!

I would advise sticking with mains chargers if you can.

 

When you start any car, push the clutch down, saves around 10-20% battery power depending on temprature.

 

regarding point three - I think if you can't be bothered to open the bonnet and undo the croc clips once a fortnight when you want to go for a spin, you probably shouldn't have an S2k..

 

I agree its not that big a deal and I did say in the post that it is acceptable, but not ideal. If you could just leave it the charger plugged in to lighter socket that would be ideal ... alas!

 

fairpoint ... make the effort, enjoy the S and take her out! 20 mins a month would not be enough though, at least 20 mins every two weeks would be better, but even then you are letting the battery charge fade. Also, people still travel for work, go on holidays etc so you still need a solar trickle charger.

 

Nah, I go to sea for 9 months of the year (normally, on a bit of a break atm), I have a trickle charger now (mains powered, obviously), but before I did, my parents started the car up every month, let it idle for 20-30 mins and then turned it off. That is all they did.

Got back and she fired into life.

Letting the battery charge fade is not a bad thing necessarily, granted lead acid don't like to be fully discharged, but I think you are under-estimating how long lead acid batteries can hold a charge.

Solar trickle chargers are a waste of time (and money).