Switching regulator charges NiMH
batteries - 12/21/00 EDN-Design Ideas Many NiMH
(nickel-metal-hydride) fast chargers use linear regulators, such as the LM317, in a current-source configuration with a charge-monitor IC. This arrangement dissipates much heat and requires considerable heat sinking, ad Design by Jason Hansen and Jim Hill, On Semiconductor, Phoenix, AZ
Temperature Controlled NiCad Charger - This circuit is for a temperature controlled constant current battery charger. It works with NICD, NiMH
, and other rechargeable cells. The circuit works on the principle that most rechargeable batteries show an increase in temperature when the cells becomes fully charged. Overcharging is one of the main causes of short cell life, hot cells pop their internal seals and vent out electrolyte. As cells dry out, they lose capacity. This circuit can quickly charge a rechargeable battery pack without any negative effects. This circuit uses a 22VDC power supply, my version 2 circuit will run from a 12VDC supply such as a solar-powered or automobile power system. __ Designed by G. Forrest Cook
Thermal Peak Detection NiCd Charger - The electric model aircraft and car industries have produced a bewildering array of field chargers for NiCd motor battery packs. These range from simple 6 or 7 cell chargers consisting of a resistor and mechanical timer, to more complex chargers with peak detection, cycling, and the ability to handle 36 cell packs __ Designed by Stefan Vorkoettert
Thermally Controlled NiCad Charger - A voltage controlled current (maximum of 1A) is used to charge a NiCd battery. The control voltage is derived from the temperature difference between the battery and the ambient air. The charge current is reduced as the battery heats up. __ Linear Technology/Analog Devices App Notes, Jun 21st 2011
Universal NiCad/NiMH
Charger - Sometimes its more convenient to recharge batteries 'in place' rather than removing them and putting them in an external charger. This device is built around a PIC12F675 (a dandy little part from Microchip). The number of cells (1 to 8) is programmed in using the one button __ Designed by Luhan Monat-Mesa Arizona
Zap Adapter - Don't throw away those seemingly un-chargeable, rechargeable batteries; they could very well be brought back to life with the aid of this simple circuit. (Tony van Roon's Tony van Roon) __ Designed by Tony van Roon VA3AVR |