Tuesday, 21 January 2014

In search of the Methuselah battery

We just (barely) survived a recent deep freeze here, and are about to enter another one on Monday. When the temperatures outdoors are hovering around the –20C to –30C (-4F to –22F) we’re not the only ones to feel the cold. My car, which had always started, even in the coldest days of previous winters, didn’t like it one bit. Or, I should say, the battery didn’t like it one bit. So there I was, stranded, until I put a bit of charge back into the battery.  The next day, the same thing. It was time to replace the battery which I found, to my surprise, to be the original equipment and 7 years old.
Most sources I checked indicated that the average life expectancy of a lead-acid starter battery was 3 to 4 years, and given the temperature extremes here that lifetime would typically be even less. Even under more nearly optimum conditions I have never had a motorcycle battery last that long, with 5 years being about the maximum, even for a well-maintained unit.
While not the much-desired Methuselah battery that will live forever, clearly my battery didn’t owe me anything.
When I started looking for a replacement I kept seeing references to new battery technologies. In addition to the classic lead-acid battery that’s been around for a century or more, some manufacturers were touting their Absorbed Glass Mat (AGM) and Gell-Cell technologies (at higher prices, of course). So to sort out the confusion I went to an excellent source I have used before who seem to know everything there is to know about batteries and can explain it in layman’s terms – the people over at Battery Stuff. (Also a great source for replacement motorcycle batteries and accessories.)
There’s some really good information in their on-site tutorials, but to summarize, all three types employ the same general principles, but AGM and Gell-Cell batteries both have the advantage of a reduction in the rate of sulfation – which is what kills your battery over time – and so should last longer. Between the two, AGM is more suitable for starter-type applications and Gell-Cell for deep cycle applications. AGM batteries will also hold their charge longer than a typical flooded lead-acid battery, so forgetting to hook up the trickle charger when you’re going to be out of town for a few weeks is much less likely to leave you stranded with a dead battery when you return.
All of which is to say that the battery on my Dyna is nearing its end of life. It still seems to hold its charge, and I do keep it on a charger, but my next battery will definitely be an AGM type.


  1. I have one of the Odyssey batteries in my bike and it works well. Keeps a charge even during periods of non-use. For this winter, I changed to a regular flooded, lead-acid car battery in the sidecar as I wanted more capacity. There were many times last year when the motorcycle battery was unable to turn over the engine at sub-zero (F) temperatures.

    I just checked over the weekend and the Odyssey is still fully charged. I still have it in the bike with the negative terminal disconnected. I figure that I could always use it to jump start the bike if I really ran down the car battery.

    As far as battery life, my diesel truck came with AGM batteries when new and they are now almost 9 years old. Even at 0F they will still start the engine even without being plugged in. So long life seems to be a benefit of the AGM batteries.

    1. Richard - Thanks for the feedback. It confirms my choice.

  2. Canajun:

    I knew there was a reason we don't need those fancy batteries. I generally put my bike(s) on battery tenders/maintainers all year around. When the bikes are parked, they are also plugged in (all the time). We don't get cold enough here to challenge the batteries. and as long as you buy brand name, they last years.

    Last year I bought a new Yuasa for my Beemer as I don't think the original owner took care of it and it wouldn't go to full charge but even though it worked okay, I didn't want to take the chance.

    For you, it wouldn't make sense to buy it until your riding season starts. Have you checked into the Shorai, low discharge type ?

    http://shoraipower.com/ lithium battery technology

    but you need to buy their special charger as the others won't work with this battery

    Riding the Wet Coast

    1. Bob - The special charger requirement is a game breaker for me. I need to keep it as simple as possible - and ensure an ongoing role for the 4 battery chargers I already have.

  3. AGM batteries are very different from traditional lead-acid batteries. For example, they are leakage free and need a lot less maintenance. These advantages compensate the higher price.


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