I have a bike battery of some flavour in my indy, which suffered from last winter in a garage (due to moving house and it not coming with me immediately)

On charging with a battery conditioner thing it'll spend a few days slowly building up to 12v or so, but once unhooked from the charger it seems to self discharge over a couple of days and generate a bit of heat.

Is it dead, or is there some way I can perform magic?

Cheers.

New battery required end of story.

Wot he said

You have ruined your battery I'm afraid

Sadly if its taking that long to charge its scrap

Dont know if my battery is the same as mine but after a couple of months sitting there it had lost build in cells and was screwed.

I went to halfrauds and got some de promised water and some battery fixing tablets. Popped it all in and gave it a charge. Hey presto working battery. total cost is £6.

Worth a shot?

Those tablets work if the plates are a bit furry, as proved just the other day with the FILs MGB, but if the plates are all wibbly, don't waste your £6!

Figured as much, ah well.

The smaller the battery used in any particular application the shorter its' life expectancy. How long any battery will last is a lottery only 20% of batteries last 4 years or more but there are factors that the user can control to extend the life of a battery.

(1) Don't deep discharge the battery, if more than 30% to 40% of a battery's charge is used it will significantly reduce the amount charge a battery will hold when when recharged.

(2) If the battery has had a significant amount of charge taken out it recharge it as soon as possible.

(3) Charging at a low amps rate is better for the battery than fast high rate charging. How fast you can charge a battery depends on its' size as a rough guide divide the charge capacity in amp hours by 12, ie Large Motor cycle battery 14 ah charge at 1.2 amps or less 1.6 litre Mondeo battery 45 charge at 4 amps or less, 2+ litre Diesel car battery up to 8 amps.

(4) Temperature, lead-acid batteries work best around room temperature, in sub-zero conditions the battery's output is significantly reduced, in hot conditions the batteries life is reduced.

(5) Using a boost charger bad for the battery and if the battery is fitted to car can be bad for the electronics, so if have to boost charge a battery disconnect the battery first.

(6) Using proper heavy duty jump leads to start from another car is likely to be less damaging than using a booster setting on a charger.

(7) It is best to use a smart electronic controlled for float charging, if you don't have an electronically controlled charger periodically (ie every 2 weeks) put the battery on a low rate charge for 2 hours or so. You can roughly assess the charge by measuring the voltage across battery but no load voltage depends on temperature as the temperature falls the voltage across the terminals is reduced. Officially a battery should be rested after charging for 12 hours before measuring the no load voltage but a couple of hours after should be enough to get a working reading.

As a rule of thumb at in typical UK winter temperature (ie 0c to 10c) a rested voltage of 12.62v indicates the battery is fully charged, (modern enhanced chemistry batteries might read slightly higher up to 12.8v) if the battery reads less than just 12.6v put it on a low rate charge for a couple of hours. 12.4v or less would indicate less than 75% charge and the battery needs a longer time on charge. 12.3v or less indicates a heavily discharged battery try a long low rate charge to recover the battery. More than 12.6 (or 12.8) volts across the terminals of rested battery indicates an overcharge. Overcharging is bad for the battery and dangerous as it can lead a hydrogen explosion.

When buying a battery the main considerations apart from price are quality, Cold Cranking Amps (cca) and charge capacity.

On average big brand name premium range batteries last longer the budget brands, batteries with 4 year warranties last longer than unknown name with shorter warranties.

In any given application on average those batteries with higher ah and cca ratings (i.e. bigger or heavy duty) battery will last longer than lower rated batteries.



[Edited on 28/10/12 by britishtrident]

Good advice from BT...

I changed my battery on the Viento this spring. It had done 5 years, which I thought was pretty good.

I use an Optimate charger, and I dont leave it on all the time during the winter. I just check and charge every 3-5 weeks. especially in the really cold parts.