Posted: March 1, 2013
The cost is still higher than traditional batteries, but the new technology is gaining ground.
Boaters considering upgrading or replacing a battery bank will find, after doing a bit of research, there are major changes taking place in battery technology.The newest technology — lithium ion — has now made its way into batteries with enough storage capacity to be used as house batteries. The use of this technology yields batteries that are much lighter and smaller than current battery types. Lithium is the lightest non-gas element in the periodic table. It’s so light it floats on water. A cubic foot of lithium weighs 62.4 pounds vs. about 710 pounds for a cubic foot of lead.
The reduced weight — 61 pounds vs. about 168 pounds for lead-based batteries of equal capacity — and physical size of the lithium batteries makes installation and electrical updates much easier.
Lithium-based batteries are a relatively new technology, with the non-rechargeable versions coming onto the scene only in the 1970s. Contrast this with lead-acid technology, which has been around since the 1880s. Because of their light weight and small size, non-rechargeable lithium-ion batteries were first widely used in hand-held electronics.
The advent of rechargeable lithium battery technology in the early 1990s brought players such as Sony and Asahi into the field. Developments in lithium technology came fast and furious, and boaters and lawyers are now beginning to benefit from it: boaters because we now have much lighter batteries; lawyers because of the various lawsuits battery developers have launched against each other claiming technology rip-offs.
Lithium-based batteries have reached a level of acceptance such that, in 2011, lithium-ion batteries accounted for two-thirds of all portable secondary battery sales in Japan. It is rumored that Samsung and Kyocera are jointly working on a project that will advance lithium-ion technology dramatically.
There are advantages to lithiums other than weight and size. They can be charged faster — about one hour from “empty” to full — and exhibit no memory effect. The good lithiums can be recharged up to 2,000 times, compared to about 700 charging cycles for the deep-cycle batteries (or golf-cart batteries, as they are often called) currently favored for house batteries. Lithium batteries are sealed and require no maintenance other than making sure the contact connections are clean.
Lithium batteries big enough to be used as house batteries have a couple of disadvantages. The first is they are not nearly as widely available as the more traditional battery types. The second disadvantage is cost, about $2,750 for the largest of them. This is about three times the cost of an equivalent top-quality sealed AGM battery. It is likely that availability will go up and cost will come down as the technology develops and sales volume increases. Lithium manufacturers point out that with battery life about three times that of the more traditional batteries, overall cost, over time, will be comparable, and the rapid charging capability will result in less generator charging time and, therefore, less cost.
Stored Energy Products Inc. (storedenergyproducts.com), a battery supplier in Lake Worth, Fla., is one of the U.S. distributors for a line of lithium batteries made in Europe. “These batteries, with their light weight and small footprint, are ideal for the marine market,” said Stored Energy’s president Clinton Beiter. “As volume increases, the prices will come down.”
Anthony Crane, a director of Britmar Marine Ltd., of North Vancouver, B.C., who distributes the same battery, agrees with Beiter. “These batteries are cost effective over time, and costs will reduce as availability increases.”
Traditional battery technology — flooded lead acid, AGM and gel — continues to perform as well as house batteries, and with the major difference in cost between them and the lithiums, they will likely continue to be the house battery technology of choice, at least for now.
