Overcharging always leads to battery health concerns. It makes them swell or melt over extra charging. However, if this does not take control in time, it may also affect the users too. Moreover, overcharging makes the battery casting too hot, which creates volatile hydrogen in the sealed cells of the battery. Thus, turning them into bad cells. Fortunately, you can easily prevent your batteries from overcharging through battery indicators. This article, however, gives a brief detail about how these battery charger indicators work and how you can make one.
Battery charger indicator refers to a type of device that shows battery status using LCD and LED. This indicator is specifically used to see the left battery level. You can see the battery indicator in the form of bars or dots in smartphones. That perfectly shows the status of the remaining battery present. This battery indicator contains a circuit that determines the device battery over the glowing LED numbers and then shows it over the LCD.
Heyer first introduced this advanced concept to the people in 1938. His concept simply proposed the idea of a battery level indicator that shows battery percentage. This indicator refers to the amount of voltage and power left in a battery. It uses LEDs and LCD to display the input. It determines the batter level through the glowing number of LEDs and the color simultaneously. Then the LCD displays the output or the battery percentage. However, this battery indicator only uses LM3914 IC that controls the LED and operates the LEDs. Moreover, despite using a controller of LCD and LED, microcontrollers prove best to upgrade the functionality of the circuit.
Battery Charge Indicators
Battery indicators or charger indicators refer to a type of device that shows battery percentage. Also, it shows the status of the battery in accurate visual indication form. Moreover, high-tech devices that need advanced batteries to operate already have built-in battery charger indicators. These devices include computers, tablets, laptops, calculators, smartphones, smartwatches, power banks, some game players, etc.
Mobile phones also use different types of visuals to show the battery status. Some whose status is in bar graphs. This means the higher the graph, the higher the battery. At the same time, some use percentages to show the status. Moreover, the battery charge indicator does not only show the status of the battery but also the charging mode. This means that some wearable or portable mini devices; show battery charging mode whether it’s charging right now or not. Other than that, it also shows the number of times a device needs to charge fully. This feature is included in smartphones, laptops, smartwatches, and power banks.
Furthermore, battery indicators use lights to tell the high and low status of the battery. An ideal battery system contains an integrated controller. This contains an interchangeable pack of batteries. Thus, this helps the battery indicator to give an accurate result of the battery charging status.
Make A Battery Charge Indicator Circuit
Battery charger indicators can be made through various types of methods. Thus giving the precise status of the batter. Here we have three main and common methods of making mattery indicators. These include
- Battery charging indicator circuit in percentage.
- Battery indicator circuit with IC LM3914.
- A circuit of full charge battery indicator with two transistors.
Components Required
The first circuit needs the following components:
- 1 PCB
- 5 Resistors of 1k
- 1 DC supply of max 15 V
- 1 Resistor of 15 k
- 1 Resistor of 10k
- One resistor of 47k
- Some brown and black connecting wires
Steps
The construction of this circuit is divided into four simple steps.
- First, insert all the electrical components on the surface of the PCB. This includes all resistors and LEDs. Make sure LEDs connected in series
- Once you place all the components over their places. Then start soldering all resistors, LEDs, and wires
- Then take brow wire as a positive terminal while black wire as a negative terminal. Solder them over the PCB. However, this power especially connects with the PCB.
- In the last, match all the connection points with the diagram or design. Ensure all the connections are made perfectly. Then supply power of 13 V to test the circuits. If they light up, the circuit works fine.
How does It work?
The battery indicator circuit shows the percentage of the battery in ascending form using LEDs. In this, each LED has a specific range of percentages. The first shows 20%, the second 40%, the third 60%, the fourth 80%, and the fifth LED shows 100% battery. Moreover, LEDs glow on different voltage supplies. On the supply of 5 volts, only 2 LEDs glow, while on the supply of 10V, 3 LEDs glow up. However, when the power supply reaches 13 volts, it glows up all the LEDs.
Battery Level Indicator Circuit – LM3914
This type of circuit contains an integral part, an LM3194 Integrated Circuit. This IC works on the supply of analog voltage, which linearly glows the LEDs based on the analog input voltage. Moreover, this circuit does not require the connection of LEDs and resistors in series form, as the IC can transfer the current across all the circuits equally.
Components Required
The construction of this circuit requires the following components
- 1 IC LM3914
- 1 SPST switch
- 1 Battery
- 10 LEDs ( 4 yellow, three green, and three red)
- 1 Resistor of 3.75Kohm
- 1 Resistor of 1.25Kohm
- Some connecting wires
Circuit Design
In this circuit, LEDs display the capacity of the battery in dot mode. You may choose the desired mode with an external switch. This external switch must need to connect with IC pin 9. Moreover, connect pin seven and pin 6 to GND using a resistor. This resistor determines the brightness of LEDs. The POT RV1 and R2 or resistor create a circuit of the potential divider. It does not need any external source of power supply as the POT RV1 handles the calibration.
Moreover, utilize different colors of LEDs that help in sowing the status of the batter. This red LED shows low battery status. While green LEDs show fully or almost fully charged batteries. Whereas yellow LEDs help in indicating other statuses of power. Moreover, in this, each LED shows a battery level of 10%.
How To Test & Use?
Firstly, create a connection between the circuit and the battery of 12 Volts. Set the POT RV1 and wait for it to glow. Then increase the DC input voltage gradually and see the glow of LEDs. You can also test the circuit functionality. The first LED shines over a voltage of 1.2v, and the second glow over a voltage of 2.4v. Whereas when the input voltage reaches 12v, it glows up all the LEDs. Moreover, this circuit works over a small input voltage supply. Therefore it may need some tweaks to operate correctly.
Battery Full Charge Indicator Circuit Using Two Transistors
This fully charged battery indicator lights up the LED when the battery is fully charged. Moreover, it does not need many components other than just two transistors.
LED Switching On At Full Charge
The main purpose of this circuit is to light up the LEDs as the battery of the device charges fully. Therefore, to make this circuit, you need to provide desired upper charge status. Then create a setting according to it to make LEDs light up when it crosses the set status.
LED Switching Off At Full Charge
Moreover, this circuit also allows the LEDs to turn off once the battery charges completely.
How To Set up And Use?
It’s one of the easiest circuit battery indicators to set up. First, set a high level of charging. Then supply the input voltage that must be equal to it. After that, tweak the circuit carefully using the screwdriver so that the LEDs turn off at the desired level. Therefore if the circuit manages the battery of 12v over the charge level of 14.3v, then you may tweak the pre-setting to turn off the LED over 14 volts.
Conclusion
Battery charger indicators also refer to the percentage or level indicator that is the integrated circuit for all the devices that operate on batteries. Without these devices, you may overcharge the device, which leads to damage. Or you may forget to charge the device, which ends up turning off on a very important matter.
Not only do smart devices operate on batteries, but it also serves an important role in remote battery vehicles. It is essential to know the condition of the battery every time so that it won’t end up stopping in the middle of the road and leading to unwanted accidents. Therefore, these battery indicators help the user to keep track of the battery’s health.
However, this article shows different ways to make these battery indicator circuits using different types of components. The working principle of these battery indicators must have shown you their significance in battery-operated devices. You can also try to make these indicators on your own, or you can ask manufacturers to make them for your device.
