New! Technology Store
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New! Technology Store |
rechargable batteriesWhat type of rechargable batteries should you use? There are currently 4 types of rechargeable batteries.
nickel-cadmium rechargeable batteriesNickel-cadmium rechargeable batteries have been in commercial use since 1950. The strongest feature is that it has the best cycle life. It can be recharged up to 1000 times. It also offers a good capacity and energy storage density. What do you mean by capacity? Capacity means the amount of electric charge it can produce when it is fully charged. What is energy storage density? Energy storage density refers to the ratio of the capacity to the weight or size of the battery. That means, that the higher the storage density, the more the energy can be stored in the given weight of the battery. A point to note is that cadmium is a toxic material and must be properly handled and disposed of. The chief disadvantage of nickel-cadmium rechargeable batteries is the memory effect. What is memory effect? If the cell is partially discharged and then recharged again, it may lose capacity because this action results in the formation of cadmium crystals on the anodes of the cells. How to overcome this problem? Deep discharge the rechargeable battery until there is minimum amount of energy left in it. Then charge the battery again. Be careful when you do this though. If you drain the battery until there is less than 1 volt left, you may well damage the battery. nickel-metal hydride rechargeable batteriesNickel-metal hydride rechargeable batteries have been in commercial use since 1990. Nickel-metal hydride rechargeable batteries has a storage density of 50% higher than nickel-cadmium rechargeable batteries. One key advantage for these rechargable batteries is the substitution of hydrides for the toxic cadmium. The disadvantage of Nickel-metal hydride rechargeable batteries is that they have a highest self discharge rate of all the rechargeable batteries. They lose up to 30% of the capacity in a month. Also these batteries can only be recharged up to 500 times. Much less than the nickel-cadmium rechargable batteries. Lithium ion rechargeable batteriesLithium ion rechargeable batteries offer the highest storage density of all the rechargeable batteries. On top of that, they do not have any memory effect. The cycle life of Lithium ion rechargeable batteries is still less than nickel-cadmium rechargeable batteries, but better than the nickel-metal hydride. Lithium polymer rechargeable batteriesLithium polymer rechargeable batteries offer the latest technology in rechargable batteries. These are similar to Lithium ion, but are cheaper. While the older types of rechargable batteries relied on liquid electrolytes for energy, Lithium polymer rechargeable batteries use solid polymer cells. Hence, they can be shaped into flat or rectangular packages that occupy less space than other rechargeable batteries. They are lighter and have no flammable solvent, unlike their predecessors.
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