Battery, how long can it stand idle?

[timtheenchanter]

due to having a motorcycle accident a couple of months ago, I have not been able to drive my car, and have had an automatic from the insurance.

I went to check my battery after 6 weeks, and found it had dropped it voltage to 12.2V, so I put it on charge to boost it, left the battery at a healthy 13.2V, I put my solar panel in there to keep it topped up (just one of those 500mA solar panels that plug into the socket, I connected it direct to the battery to avoid losses)

A week and a couple of days later, the battery is back down at 12.4, not as low as before, but still low.

everything in the car is unplugged, the car has no alarm, just a factory fit immobiliser.

so, is this normal, or should I go get a new battery before the winter?

Oh, its a peugeot 406 2.0HDI 110.

 

[JohnD]

solar panels are not much good

give it a another go with the charger before making up your mind.

 

[Lemond2008]

If you are planning on leaving it stood for a while longer, I would consider disconnecting it totally - that is the only way to ensure nothing is draining it!
Alternatively, just start the car every week and run it up for 5-10minutes.

 

[JohnD]

... just start the car every week and run it up for 5-10minutes.

...if you want plenty of acid condensation in the engine

 

[timtheenchanter]

If you are planning on leaving it stood for a while longer, I would consider disconnecting it totally - that is the only way to ensure nothing is draining it!
Alternatively, just start the car every week and run it up for 5-10minutes.

I might just do that, does anyone know if the stereo has a code?

still, a 9 days for it to reduce back down.

the solar panel isnt that bad, it keeps 2x 85 Ahr leisure batteries topped up in my caravan for months on end, I check them every 3-4weeks.

 

[blondini]

A week and a couple of days later, the battery is back down at 12.4, not as low as before, but still low...

so, is this normal, or should I go get a new battery before the winter?

Terminal voltage on a fully charged battery will quickly drop to 13.2 when taken off the charger but then slowly settle to 12.6 which is indicative of 100% charge.

12.4v is indicative of less than 75% charge, and 12.2v less than 50%.

You'd think the solar panel would maintain close to 100% charge if there was no drain on the battery? What sort of voltage is it kicking out?

 

[timtheenchanter]

it packs out about 16-18V, only at 0.5A, the voltage drops if any load is put on it to around 14-15V depending on the amount of light.

the battery is probably the original, its a 53 plate vehicle.