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Car Battery Warmer Circuit

Last Updated on May 16, 2026 by Swagatam Leave a Comment

car warmer circuit

The main objective of this car battery warmer circuit is to make sure that even in extremely low temperatures, the battery can be charged and discharged satisfactory. The design idea was requested by Mr. Elias, as I have explained below. Design Request and Specifications My plan is to control a silicone heat pad that runs […]

Filed Under: Automobile Electronics Tagged With: Battery, Warmer

Use this Battery for 50 Years without Charging

Last Updated on May 17, 2026 by Swagatam 4 Comments

betavolt battery

A novel battery technology, developed by Beijing-based firm Betavolt, has been introduced. It boasts an astounding 50-year lifespan without the need for maintenance or charging. With 63 radioactive isotopes contained in a module the size of a penny, this ground-breaking nuclear battery is a leader in the field of atomic energy miniaturization. https://twitter.com/Byron_Wan/status/1746801325722239367/photo/1 Advancements in […]

Filed Under: Battery Charger Circuits Tagged With: Battery, Charging, without, Years

Battery Low Voltage Alarm Circuit

Last Updated on January 3, 2024 by Swagatam 4 Comments

table 1

Despite its simplicity, the Battery Low Voltage Alarm circuit has a very important function. It forewarns you of approaching battery failure so that you may run to the store and get replacement cells before your equipment stops functioning entirely. Because of its compact size and low current need, it may be integrated into the devices […]

Filed Under: Security and Alarm Tagged With: Alarm, Battery, Voltage

Solar Battery Charger using LM339 Comparator

Last Updated on December 4, 2023 by Swagatam 13 Comments

LM339 solar battery charger circuit

This small LM339 based solar battery charger setup is designed to optimize the charging of your battery using any solar panel while protecting it from accidental overloads. Considering the extended battery life it allows you to achieve, it is an investment that quickly pays for itself. Circuit Description Our setup is nothing more than a […]

Filed Under: Solar Controller Circuits Tagged With: Battery, Charger, Comparator, LM339, Solar

Gel Cell Battery Charger Circuit [Constant Current, Constant Voltage]

Last Updated on May 17, 2026 by Swagatam 42 Comments

Fig 1

In this post I have explained what are gel cell batteries and also learn how to build a specialized charger for charging a gel cell battery, with full calculations. The proposed circuit works in two modes: it starts charging a discharged gel cell battery with constant current, until the full charge voltage is reached across […]

Filed Under: Battery Charger Circuits Tagged With: Battery, Cell, Charger, Constant, Current, Voltage

3 LED Battery Level Indicator Circuit

Last Updated on May 17, 2026 by Swagatam 58 Comments

car battery indicator circuit

The proposed 3 LED battery level indicator can be typically used for monitoring a 12 V lead acid battery charge level, through 3 distinct LED illumination. The entire circuit is built using just a couple of BJTs , a few zener diodes, resistors and LEDs. Different Ways to Check Battery Voltage A hydrometer is perhaps […]

Filed Under: Battery Charger Circuits Tagged With: Battery, Indicator, LED, Level

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