Solar panels to charge 12v battery

[bill_5078178]

I am having a problem with my leisure battery. The van is a senator Oklahoma 2003 model and if I leave the battery in the van when I put it back in storage, it is flat when I come to go away again. So to date everytime I put the van back in storage I take my battery home and it is then on trickle charge till I go away again. It is 110v and quite heavy. Would a solar panel that could connect to the battery, left in the van, solve my problem? One that I could take on and off the van when required.

 

[Chris4]

Yes, it could work. The panel would need to be large enough to charge a large battery. I would suggest 30/50 watts min. It would need to be positioned so that it is exposed to full sun. You would also need a charge controller to prevent it from over charging. Try www.windandsun.co.uk, they do some good quality panels. One problem though. I've heard that there is a world shortage of the silicon that goes into these panels so prices are going up.

 

[Richard_5079280]

Hi Bill

Having read your letter with interest ,it's the same problem I had, having to take the battery to the house for recharge. I also have experimented with solar,although they are very good they can be expensive to buy .

I found that if you disconnect the battery from the terminals,you will find the discharge greatly reduced therefor

there's no need to charge the battery between outings , and it's cheeper than buying solar.

Richard

 

[emmerson2]

re battery going flat in storage. Others have suggested ways of keeping it charged, but have you checked to see WHY it goes flat? There must be a discharge somewhere, or the battery is shot.Mine does not loose charge over the winter. Emmerson

 

[rob_jax]

Emmerson,

All batteries, especially rechargeable batteries, self discharge due to internal chemistry actions, and at different rates depending on the cell chemistry.

For instance a rechargeable NiCAD (power drill) will discharge by 1% (or more) of it's capacity every day, a non-rechargeable alkaline battery will totally self discharge in 10 years, and a GEL leisure battery will self discharge by about 3% per week - flat in 1/2 year or sooner.

Bill - Solar Panel - Sounds like a good idea

If your GEL battery is fully charged when you put the van in storage you will only need a small panel (about 5 to 10 Watts) to keep it 100% topped up. During day light hours in the UK this will deliver around 0.2 to 0.5 Amps, which is enough to combat the night and day 0.1 Amp self discharge.

Small power panels don't need a charge controller, will maintain a fully charged battery, but won't recharge a flat battery.

If you fit a more powerful solar cell, say 30+ Watts, to charge a flat battery whilst in storage, don't forget Chris's recommendation for a charge controller to limit the current once the battery is fully charged.

Robert

 

[emmerson2]

Rob_jax, Thanks for that info.

Bill, now you've got the perfect excuse to use the van more often!!! Emmerson