Battery Charging Options [57]

By David Winkworth

Electrical devices are part of a sea kayaker’s world these days: electric pumps, radios, mobile phones, GPS units, EPIRBs, digital cameras….the list goes on. The technology is there for us to use but to use it effectively we need batteries in good charge condition. In Issue 55 of this fine publication, Stephan Meyn penned an excellent article on “Taking Care of Batteries.” This piece follows that up with a couple of other options for sea kayakers to keep their batteries in good charge condition.

For short trips we usually just charge up our devices such as pump batteries, mobile phones etc, or put a fresh set of batteries in the radio. That is usually OK for the small amount of use of the device. For a slightly longer trip we may carry a spare battery or two. However, when the trip stretches out to a month or two or more and weight of gear becomes a consideration, we have to make a few decisions. Cost also becomes a consideration as some battery types are not cheap and any spares we buy may never be used again. The cheapest and lightest options are to recharge our batteries either with a solar charger or with other batteries. Both of these options have advantages and disadvantages. Individual paddlers need to assess these when making their choice.


The Megapulse 12 Volt Solar Battery Charger

If going solar is your preferred option, this is a very neat little set-up. The panel is encased in e.v.a. resin and weighs a low 90 grams. It measures 165mm x 115mm and is only 4mm thick. Output is a relatively low 145 milliamps at 13.8 volts. Manufacturers claim the panel is self regulating and comes with built-in blocking diode protection. Kate Yeomans of Brisbane used two of these panels to keep her video and mobile phone batteries charged on her solo Brisbane to Thursday Island paddle a few years ago. Kate found that one panel didn’t give her quite enough charging capacity but two of them were just right. She stuck them to the foredeck of her kayak with silicone and ran the wires into the front hatch where she connected her batteries. Simple.

I have bought two of these panels (about $75 each) and plan to make a shallow recessed molding for the deck of my boats in which to fit them, connecting them up to a bulkhead-mounted cigarette lighter plug within the hatch. The decks of sea kayaks can be pretty busy with hatches, spare paddles, maps and the like and finding space to fit panels can be difficult. The small size of these panels and their lack of a frame makes them easy to locate on the deck. I think one of these panels would make a good top-up charger for an electric pump battery on an expedition. Actually, you could connect up permanently to a pump battery. Although, I haven’t connected my panels up yet, so I can’t say how they would go when paddling in the southern states where sunlight, especially in winter, is not as strong as it is in Queensland for example.

Batteries to Charge Batteries:

This is the cheap option but it works really well. Last year I looked into Satphone battery charging systems for our Cairns to Darwin Paddle. I bought a small gel cell battery – the smallest I could get – about 1.2Ah – and found that it weighed 600 bloody grams! Not only that, it could only be recharged with a special charger. I junked that option as being too heavy and too specialized and, after chatting with Andrew (Professor) Eddy I bought a 10 AA battery holder from Dick Smiths for about $3. I also bought an inline cigarette lighter plug and a couple of alligator clips.

Ten AA batteries, weighing a total of only 250 grams gave me a nominal 15 volts and by plugging the 12 volt charger lead from my phone into the cigarette plug, I could get multiple charges from the battery set. I could also connect up to any 12 volt battery with the alligator clips. Before our trip we sent off food drop parcels which included spare sets of AA batteries.

The downside of this system of course is the use of a set of batteries for charging and then having to “paddle them out” but it’s a simple system and it worked well.

If you use either of these systems, make sure you get the polarity right before hooking up….and that the system will work with your device!