Battery
From dKosopedia
There are several types of battery each with different characteristics of power retention, weight, toxicity and cost. The basic types are:
- alkaline batteries come in rechargeable and disposable kinds. Disposable alkaline batteries are toxic and must be disposed of properly, and are a major environmental concern
- nickel-cadmium batteries are rechargeable but only to a limit of typically 1000 charges;
- lead-acid batteries, currently used in forklifts and other vehicles, and in some telecom devices like cordless phones, are relatively heavy and must typically be kept fully charged, as running them down damages them; they contain toxic materials
- lithium-ion batteries, currently used in portable computers and some other mobile/worn devices that will often run down far from power sources, are light but expense
- hydrogen fuel cells come in sizes ranging from a car battry to a tractor trailer container; they are almost always charged from electricity and release their charge as electricity - and waste heat; they are less toxic than almost any other option, and more rechargeable, and hold their charge longer, and can be directly charged from liquid hydrogen or a number of other processes (see direct charging of fuel cells) using methane, oil, biomass including sewage, and potentially coal - though this isn't here yet.
Fuel cell innovation is thought to be one way to address climate change, and is in any case widely believed to be the key to the hydrogen economy.