Self Powered Battery Tester

Self Powered Battery Tester
This self powered battery tester circuit runs a fast battery test without the need of power supply or expensive moving-coil voltmeters. It features two ranges: when SW1 is set as shown in the schematic diagram, the device can test 3V to 15V batteries. When SW1 is switched to the other position, only 1.5V cells can be tested. (more…)

Versatile AA-Cell Battery Charger

Versatile AA-Cell Battery Charger
This is the circuit design of AA-Cell battery charger that can be used to charge six AA batteries at once. An integrated circuit of LM317 voltage regulator is configured as a constant-current source. It is used to supply the 50 mA charging current to S01-S06, an array of AA-cell battery holders. Each of the battery holders is wired in series with an LED and its associated shunt resistor. (more…)

Electric Car Battery Charger

Electric Car Battery Charger
This is the scheme diagram of electric car battery charger. As shown the circuit is a conventional power supply, followed by a regulator LM338 which is controlled by an operational amplifier which is responsible for controlling the state of charge to detect the precise moment that must stop and actuate the LED indicator. The resistive divider enables three stages, first take the reference voltage for the operational amplifier and, on the other, control the regulator LM338 through the output

Battery Discharge Monitor

Battery Discharge Monitor
Above circuit diagram is a battery monitor circuit which detaches the load when the battery is discharged, anticipating a deep discharge which could cause permanent battery damage. The battery is automatically reconnected when a battery charger or other DC source is connected across the load. Select a relay which requires less than 100mA coil current and with contacts capable of handling the load and charging currents. (more…)

Battery Charger Powered using Single Solar Cell

Battery Charger Powered using Single Solar Cell
This is the schematic diagram of battery charger circuit that powered using single solar cell. The circuit designed using MC14011B  manufactured by ON Semiconductor. CD4093 can be used to replace MC14011B. Supply voltage range : 3.0 VDC to 18 VDC. (more…)

Lithium Ion (Li-Ion) Battery charger

Lithium Ion (Li-Ion) Battery charger
We can charge Ni-Cd or Ni-MH simply by placing a series resistor to limit current from the power source to make efficient loading. But not so with lithium ion cell (Li-Ion) which has a capacity greater than ever and don't need to be completely discharged to charge them, but require a strictly controlled charging. (more…)

12Vdc mobile battery charger

12Vdc mobile battery charger
12Vdc mobile battery charger circuit diagram can delivers up to 20 V output from the 12V car power supply, allowing a constant current charging to NiCad battery unit around 18 V max. (more…)