What's your battery system?
Posted: Nov 10, 2009 6:05 pm
I was wondering what kind of of batteries most people here use, and what their system is for carrying and storing them.
Battery chemistry is the first major question (see poll). Alkalines are cheap and readily available, but their performance is less than stellar. Lithium primaries are far better, but they are significantly more expensive. However, my research seems to indicate that their total power is about three times more than Alkalines, so you should always buy them if their price is less than three times as much, so as to get the best $/joule ratio possible. NiMH and their low self discharge brothers have good total capacity, but the upfront cost of a charger and cells is high. Li-ion is the absolute best in terms of J/gram, but it has the significant disadvantages of usually having custom battery shapes, and risk of catastrophic failures resulting in fire and explosion.
I'm also interested in what people do to manage and store their batteries, as well as how many sets they typically take with them. I've only been on a couple of trips so far, and my current setup consists of leaving a backup sets of four AAs in a ziplock bags, which in turn goes in the same stuffsack I store my backup light in. This is suboptimal, since it makes getting to the batteries difficult, they roll around loosely, the bags are fragile, and it's difficult to see whether any given set is charged or empty. I currently use alkalines, but was planning on investing on a NiMH charger with LSD cells soon. I'm also considering sewing together some cordura battery pouches with a velcro clasp. They'd hold 4 or 8 AA cells side-by-side securely, and it would be easy to indicate the charge state of a cell by putting it in with the opposite polarity facing outwards. They would be compact and superdurable, but not waterproof (not that it really matters in New Mexico).
Battery chemistry is the first major question (see poll). Alkalines are cheap and readily available, but their performance is less than stellar. Lithium primaries are far better, but they are significantly more expensive. However, my research seems to indicate that their total power is about three times more than Alkalines, so you should always buy them if their price is less than three times as much, so as to get the best $/joule ratio possible. NiMH and their low self discharge brothers have good total capacity, but the upfront cost of a charger and cells is high. Li-ion is the absolute best in terms of J/gram, but it has the significant disadvantages of usually having custom battery shapes, and risk of catastrophic failures resulting in fire and explosion.
I'm also interested in what people do to manage and store their batteries, as well as how many sets they typically take with them. I've only been on a couple of trips so far, and my current setup consists of leaving a backup sets of four AAs in a ziplock bags, which in turn goes in the same stuffsack I store my backup light in. This is suboptimal, since it makes getting to the batteries difficult, they roll around loosely, the bags are fragile, and it's difficult to see whether any given set is charged or empty. I currently use alkalines, but was planning on investing on a NiMH charger with LSD cells soon. I'm also considering sewing together some cordura battery pouches with a velcro clasp. They'd hold 4 or 8 AA cells side-by-side securely, and it would be easy to indicate the charge state of a cell by putting it in with the opposite polarity facing outwards. They would be compact and superdurable, but not waterproof (not that it really matters in New Mexico).