solar battery trickle charger

[sundancer9000]

Hello i have been considering buying a solar trickle battery charger. i have seen some of these as cheap as 30 sterling in amazon!!
This is for a Merryfisher 925 that has 2 large batteries. Problem is that i am rarely near shore power and rely heavily on battery power. i think a trickle charger will keep everything nice.
Can anyone advise on the amps etc as in the best specification i should look for as i am not familiar with the electronic terminology.
Many thanks in advance as always. Stan.

 

[pappaecho]

Two large batteries will require quite a bit of charge, specially in the winter.

You would really need 40-60 watts to give an effective charge, and then you really would need a charge controller, because in the summer it will overcharge unless regulated.

I would suggest starting at Ebay, as there is a wide range of products at good prices.
A 60 watt panel would need a 5 amp controller

 

[sundancer9000]

Many thanks i will let u know how i get on

 

[sarabande]

I'm guessing that you have a combined battery capacity of something like 200AHr ? Do you just need a trickle charge ?

It's a rough standard that 10% of the capacity is the required solar output, so a minimum of 20 watts will keep the batteries topped up, but will not re-charge a partially discharged pair unless it is given a lot of time to do so.

Best to go for a bigger panel, plus a regulator, as suggested by pappaecho, unless you need just for trickle.

 

[darren_v8]

I think they're good, I just use a small car solar panel to keep the battery in my little boat topped up

 

[Searush]

I think they're good, I just use a small car solar panel to keep the battery in my little boat topped up

I have two of those, one for the boat & one for a motorhome. Both items are liable to stand for weeks at a time & are susceptible to slow battery discharge.

The 10-15 quid 10w chargers connected directly to the starter battery by croc clips all the time, and mean that starting is never a problem. Once started, the engine soon recharges all batteries. The S Panle output is so small that no regulator is needed & even in the coldest, gloomiest winter (like last year) the engine started first try, thanks to a healthy o/p from the trickled battery.