Batteries

[derekgillard]

This is my first season with a new boat and we have a Rutland wind Vane. We live on a swinging mooring and it keeps the batteries charged very well.

I have been advised that as my battereis have been charged all season I should discharge them over the winter, it has been suggested I do this when she is out of the water.

Do you agree? Do Modern batteries need to be discharged or can I just leave them?

PS they were new in 2000!

Thanks in advance

Del Buoy

 

[VMALLOWS]

Who on earth gave you this advice???? I can only assume it is someone hoping to sell you some new ones. The worst possible thing you can do is discharge them. The important thing to do is keep them fully charged!!. Maybe, to be kind, someone is confusing lead-acid batteries with small NiCads which some people believe suffer a 'memory effect' if not occaisionaly fully discharged.

 

[Chris_Stannard]

I do not agree with VMallow's advice, most battery authorities say that batteries should be normally kept fully charged but should be deep cycled about once a year. If you get the PBO hand book on electrics it tells you how to do this. If you take the batteries out in the winter this can be done ashore.

The submarine service, before they went nuclear, had a regulaar routine of deep cycling their lead acid batteries to keep them operating at optimum efficiency.


Chris Stannard

 

[ccscott49]

It's a good idea to deep cycle your batteries once a year, using a good three stage charger, this will get everything, churning up nicely inside and help stop sulphation etc. You do not need to take them out of the boat, leave them fully charged and give them a top up charge, once a month at least, that should keep them nice and healthy.

 

[ccscott49]

It's a good idea to deep cycle your batteries once a year, using a good three stage charger, this will get everything, churning up nicely inside and help stop sulphation etc. You do not need to take them out of the boat, leave them fully charged and give them a top up charge, once a month at least, that should keep them nice and healthy. IMHO

 

[VMALLOWS]

I think I probably read things too literally.........'discharge them over the Winter'. Too many years writing test procedures which would be picked over for any excuse by technicians and their managers.

Yes, of course YOU were going to re-charge them immediately, but there might be some who might take the instruction literally!

I still feel that a good (so called) 'equalisation' charge will do the stiring up bit adequately without the need for a full discharge.

If you really want to, do as I used to do with miners lamps in the 60's to get a few more months out of them: charge fully; drain out electrolyte; rinse with water (preferably distilled, but the water was soft enough in Wales); refill with new electrolye. This particularly helped with lead-acids where the sulphate deposits at the bottom eventually short out the cells. However it also worked with 'tired' NiFe wet cells ('nickel-iron' .. but actually NiCd by then).

Reminiscenses over. (but we really did have ponys and acetalyne lamps as late as 1966!)

 

[ccscott49]

I used to buy my carbide from the miners in Lancashire in the late sixties for potholing, they had good carbide lamps aswell, we could sometimes get one, I've still got mine! I also had an exide miners lamp, with lead acid battery, some of the lads had stainless cased NiCads, they were also used as emrgency firing batteries for centurion tanks! I know I used to steal them! Now hows that for reminiscing and a load of useless information! Eh? /forums/images/icons/smile.gif