Batteries are the lifeblood of boats – especially for cruisers – and we’re all looking for the best way to get maximum value out of our battery bank without sacrificing comfort. (Who likes cooking in the dark? Not me.) While most cruisers know the basic tenets of battery maintenance – for example, don’t let them dip below 50% capacity – more advanced techniques are harder to discover.

Until now. John Harries of Attainable Adventure Cruising has put together a great article summarizing how to best extend battery life. He learned his tips through real experience – after replacing his battery bank 3 times in 4 years, he decided to turn his frustration into a project, and has shared the results on his site.

Harries starts with the “basic” tenets of battery maintenance:

1. Don’t regularly discharge your batteries over 50% of rated capacity
2. Charge your batteries back to at least 80% of capacity after every discharge cycle.
3. Charge your batteries to 100% as often as you can.

But he then moves onto his new discoveries that have translated into significantly longer battery life:

4. Make sure you have access to shore power for at least a week after installing new batteries.
5. Don’t leave a shore power charger on for long periods.
6. Only buy batteries that can be equalized.
7. Equalise your batteries once a month or so.
8. Install a user-programmable alternator voltage regulator and reprogram it to actually fully charge your batteries.
9. Install a smart measurement system and use it.
10. Install an alternator regulator and AC charger(s) that have temperature measurement probes on the batteries.
11. Know how your batteries should be charged and how to tell they are full.

Highly recommend you read the full article – let us know if you have anything to add to the list.

Attainable Adventure Cruising