The precise battery capacity tester circuit explained in the following article can be used for testing the maximum backup capacity of any rechargeable battery in real time. By Timothy John Basic concept The circuit works by practically discharging a fully charged battery under test through constant current, until its voltage reaches the deep discharge value. […]
Battery Charger Circuits
Arduino Battery Level Indicator Circuit
In this post, I will show how to construct an Arduino based battery level indicator, where a series of 6 LEDs show the level of the battery. If you are interested in monitoring and maintenance of your 12V battery, this circuit might become handy. Why Battery Level Monitoring is Crucial All batteries have certain voltage […]
Battery Full Charge Indicator Circuit using Two Transistors
This little circuit will alert the user regarding a battery reaching its full-charge level (over charge) while it’s being charged, by illuminating an LED. The circuit uses just a couple of transistors as the main active components. Main Feature The main feature of this design is not only its mini design but also its supply […]
Op Amp Battery Charger Circuits with Auto Cut Off
In this post I have explained a two op amp IC 741 and LM358 based auto cut off battery charger circuits which are not only accurate with its features but also allows a hassle free and quick setting up of its high/low cut-off threshold limits. High current batteries can e also charged using these circuits. […]
Make this 18V Cordless Drill Battery Charger Circuit
In this post I have explained how to build and use a 18V battery charger circuit for a cordless drill machine. The idea was requested by Mr. Chibuzo. Technical Specifications The Design Whether it’s a lead acid battery, a Ni-Cd or a Li-ion, this multipurpose battery charger shown below can be applied for any of […]
How to Set IC 741 for Auto Cut-oFF
In this post I have explained how to set or adjust an opamp 741 IC based battery charger circuit for implementing an automatic cut-off for the connected battery once it reaches the full-charge level. Since I have many such IC 741 battery charger circuits posted here, the instructions will be helpful for correctly setting up […]





