Anyone recommend a decent boat motor battery and where to buy it?

Car batteries. Cheap as chips and plenty available!

From what I've read, car batteries are not a good idea for electric motors as they're not made to provide a discharge over a long period of time.
Better with a 12v leisure battery.

I just bought a motor recently and got one of these 88ah batteries ....
Electric outboard battery 88ah 3yr wrnty sealed calcium on eBay (end time 06-Jul-10 17:26:18 BST)

At £53 including next day delivery it's a steal and the service provided by the seller was excellent.

I would not recommend anything less than 110ah for a battery that is to be used on an electric motor. have a look here, i recently bought one of these and the service was excellent, included in the price is VAT, NEXT DAY DELIVERY AND A 3 YEAR WARRANTY it is a decent price for a top grade battery that will last for years.



Caravan Batteries, Boat Batteries & Leisure Batteries - Lucas 12v 113ah Ultra Deep Cycle Leisure Battery

Robbie

Depends on the power of the motor, the weight your towing and how long you need the motor to run.
To give you some idea, I used my 88ah battery last week.
I have a 40lb thrust motor and I was out on my own.
I used the motor for about 40 minutes on full power and maybe 10 minutes on low power in a light breeze for most of the day.
When I checked the battery voltage that night, I'd used about 10% of its capacity.

Thanks chaps you are in the realms of "why didn't I ask that before"

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an interesting mix of apathy and panic

Clive M

Would agree with Robster regarding the 110 amp being best. Down side is their weight, the lucas 105 amp is quite a bit smaller than the 113 amp and probably a fair bit lighter. I would probably go for it, have never run out of power on 110 but have on a 90.
A good automatic charger also essential, see the posts on Battery Charging Advise
Advice on which chargers on this link Battery Charger Advice

These two factors are why you used a small amount of battery power , now if there were two of you in the boat on a fair sized loch in windy conditions things would be different. but saying that everyone to there own , im just saying that surely it is better to be carrying enough power for those circumstances arising ?

Robbie

So how does the day to day stuff with the monitoring and charging work out

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an interesting mix of apathy and panic

Clive M

True.
The places I fish aren't that big so the 88ah is more than enough but yes, I can imagine if your pulling more weight and travelling long distances you may need more.
The battery manufacturers recommend not discharging below about 40%.