Nowhere really to put a second battery - the front compartment of the single jockey console is basically full with the single battery and oil tank for the E-TEC, I wouldn't put it in the compartment under the seat where the fuel is (done the 'nervous trip home with the battery covered in petrol wondering if my knackers were about to go up in flames' thing on my old boat, never again) and under the seat pods would be too much hassle to install.
In terms of plan B if it goes quiet at the blunt end, handheld VHF, PLB and a pull start aux are all independent/permanently on the boat.
I'm not particularly worried about stopping it and it not starting again as I rarely stop it at sea, and the cold start on launch is the biggest load it would get with the lowest state of charge, so it was more to gauge a sensible planned replacement date.
Thanks for the input.
A Boat is a hole in the water, surrounded by fibreglass, into which you throw money...
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