Switchless NiCd-NiMH Battery Charger
This circuit may be used to replace the single current limiting resistor often found in dirt cheap battery chargers. The alternative shown here will eventually ...
Storage Battery Exerciser
A motorcycle or boat battery that is not needed over the winter is usually charged before being put away for the winter, after which it remains standing unused ...
Solar-Powered High Efficiency Battery Charger
This is a simple NiCd battery charger powered by solar cells. A solar cell panel or an array of solar cells can charge a battery at more than 80 % efficiency pr...
Solar Panel Based Charger And Small LED Lamp
You can save on your electricity bills by switching to alternative sources of power. The photovoltaic module or solar panel described here is capable of deliver...
Self-Powered Fast Battery Tester Schematic
FET Q1 provides a constant current generator biasing LED D1 and Q2 Base. In this manner D1 illuminates at a constant intensity, independent of battery voltage f...
NiMH Charger For Up To Six Cells
It is impossible to imagine present day society without any batteries. Count the number of gadgets in your house that are powered from batteries, you will be st...
Nicad Charger Uses Voltage Cut-Out
This circuit charges two NiCad cells with a constant current and features dual charging rates, voltage cutoff and an audible alarm. The circuit is powered by a ...
Low-Power Car/Bike USB Charger
We tested a regular charger and found that it consumed 13mA with no load. Like many others, it has an integrated power LED and that would contribute significant...
Low Cost Battery Condition Indicator
This design combines power-on and low-battery indication, can operate with any battery voltage up to 15V, has very low current drain (2mA or less) and costs les...
Low Battery Indicator II
This circuit indicates the remaining battery life bAy varying the duty cycle and flash rate of an LED as the battery voltage decreases. In fact, the circuit act...
Lithium-Polymer Peak Charger
This circuit was developed to charge the Lithium-Polymer cells used in a model aircraft. Lithium-Polymer cells are incredibly lightweight compared to Ni-cad bat...
Lead Acid Battery Charger 1
Except for use as a normal Battery Charger, this circuit is perfect to `constant-charge` a 12-Volt Lead-Acid Battery, like the one in your flight box, and keep ...
Internal Resistance Tester For Batteries
This circuit is designed to check the condition of lead-acid and gel cell batteries with capacities greater than 20Ah. It switches a load of about 18A at a rate...
Hyper-Simple Battery Capacity Tester
The circuit described here is eminently suitable to indicate the capacity of a battery. We use a cheap electric clock for this. By connecting a resistor across ...
Float Charger For NiMH Cells
Although not a new device, the LM317 is still a high-performance regulator. Its output voltage is essentially immune to fluctuations in load, supply voltage and...
Car and Motorcycle Battery Tester
Going camping nowadays involves taking lots of electronic equipment whether for day to day running or for fun and entertainment. Most of the time a charged lead...
Battery Charger Regulator
Most off-the-shelf car battery chargers cannot not be left connected to the battery for long periods of time as over-charging and consequent battery damage will...
12V Lead Acid Battery Desulphator
Lead acid batteries often fail prematurely due to over-charging, under-charging, deep discharging and low electrolyte level. All of these can lead to sulphation...
Solar Panel Optimizing Battery Charger
Figure shows the V-I curve for a typical solar panel (Sharp ND-224U1F), and output power under different lighting conditions. The solar panel behaves like a con...
LiPo Batteries
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