OWNER'S UPGRADE

‘WHEN I SWAPPED LEAD ACID BATTERIES FOR LITHIUM I SAVED SPACE AND MONEY’

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SIMON HARDAKER has been sailing for decades, enjoying everything from the thrills of racing catamarans around the cans to competing in offshore Fastnets. Most recently, he has sailed across the Atlantic twice in a Beneteau Oceanis 50.

His training as an artificer (electrical engineer) in the Royal Navy has proved invaluable as he aims to repair and maintain the boat during his adventures – especially when crossing an ocean where help could be thousands of miles away. Here he explains how he went about evaluating a change to his domestic batteries, from lead acid to lithium, and the issues that had to be addressed to complete the upgrade.

DIAGNOSIS: We bought our boat, Cassini, a Beneteau Oceanis 50, in 2022 intending to live aboard for long periods from the summer of 2023. After a winter overhaul and a few shakedown cruises to Cornwall and the Channel Islands that spring, it became clear that our existing domestic bank battery would need to be renewed before we set sail for our planned cruise to the Caribbean later in the year.

Our existing lead-acid batteries were AGM type. AGM or Absorbent Glass Mat, is a battery type and construction that is sealed and low maintenance, unlike the old ‘flooded’ cells that need to be topped up with distilled water from time to time. Our AGM batteries were charging well enough, but the rate and depth of discharge was fast and low. The voltage regularly fell off to less than 50 per cent. This could have been the loads we subjected the battery to, or the batteries themselves reaching the end of their useful life. Either way, they required renewal to meet expected demand for the forthcoming liveaboard period...

CHARGING CYCLES