This level battery indicator circuit that lets you know the battery level of a device from the number of LEDs that are glowing, it uses ten LEDs in all. So if three LEDs glow, it indicates battery capacity of 30 percent. Unlike in mobile phones where the battery-level indicator function is integrated with other functions, here only one comparator IC (LM3914) does it all. continue reading…

Optex Campower LI5000 is an universal battery charger, a portable model which pulls out to reveal adjustable, electrical contacts that can be maneuvered to fit various battery sizes. Optex Campower LI-5000 will be available starting from May and will cost around $89.99 and can be used worldwide, at main power supply voltages between 100V and 240V and can gain its power via AC, 12V or USB. continue reading…

As per manufacturer’s data sheets, a 12V rechargeable lead-acid battery should be operated within 10.1V and 13.8V. When the battery charges higher than 13.8V it is said to be overcharged, and when it discharges below 10.1V it can be deeply discharged. A single event of overcharge or deep discharge can bring down the charge-holding capacity of a battery by 15 to 20 per cent.
It is therefore necessary for all concerned to monitor the charge level of their batteries continuously. But, in practice, many of the battery users are unable to do so because of non-availability of reasonably-priced monitoring equipment. The circuit idea presented here will continue reading…