SOLAR NICAD CHARGER AA OR AAA CELLS Cat No: AEE-87.2221

$28.00

SPC-4 Charger for 2 to 4 AA size batteries When using the SPC-4, pleasenotethaLall battery slots must be filled. If less than 4 batteries are being charged, the unused slots must be filled with the brass shorting dowels furnished. Output of charger: 7.2 volts VOC/70 milliamp + or -5mA SC in one sun. Charging time of completely discharged AA batteries (1.2 volt per cell) is approximately 7 hours in direct sun. Less time is required for batteries still holding a percent of charge. Small batteries vary in both voltage and current output. (AA, C, D sizes) Carbon/zinc is the most common non-chargeable battery type, providing 1.5 volts output. Alkaline batteries are superior to carbon/zinc because of their longer life. Alkalines are more expensive, but have a longer shelf life, can furnish higher peak current, and resist leakage. The alkaline battery s output is also rated at 1.5 volts. Although not recommended by manufacturers, both of these types of batteries can be rejuvenated 1 to 2 times before discarding providing they are not discharged too deeply, prior to charging. When charging alkaline or carbon/zinc batteries, you should be aware of the required charge rate and time of charge required. Example: Using the SPC-4 Solar Charger, AA size pen cells should be charged for approximately 6 hours in direct sunlight. Excessive overcharging can destroy these types of batteries. Rechargeable Nickel-Metal Hydride and Nickel-Cadmium batteries are far superior and an individual who uses a large number of batteries will realize a significant dollar savings. These batteries produce 1.2 volts and can be recharged hundreds of times to their full current and capacity. This feature offsets the price many times. This battery type also maintains a more constant voltage over its cycle with extremely high current output available. Nickel-Cadmium batteries, when charged, do not have a long shelf life. In other words, they will self-discharge when not in use. They will also give very little warning when weak. Conventional batteries will steadily give less and less power signifying a dying battery. Ni-Cd and Ni-MH batteries will deliver almost full power to the end of capacity and then will fail very rapidly. Nickel-Cadmium batteries should be fully discharged and recharged every 90 days. If a Nickel-Cadmium battery is used for short cycles before recharging (example: 10 minutes use-then recharge/10 minutes use-then recharge) the battery will soon develop a "memory" for 10 minutes of capacity. After 10 minutes use, the battery will not produce sufficient power to operate the device it is used in. For this reason, deep cycling of the battery is necessary. (Discharging only to a point your device wont function.) Most of the solar cells in volume production today are made with silicon. This plentiful, natural resource makes up more than one fourth of the earth s crust and is the primary component of ordinary sand. The silicon used in the production of solar cells must be purified to a very high degree. A large part of the high cost of solar cell production results from the painstaking task of removing all impurities in order to produce the highest quality silicon. When sunlight penetrates the junction of the negative and positive layers of a solar cell, it creates a flow of electrons throughout the crystaline structure. It is this flow of electrons that produces electricity in the cell.