Automatic 12v Portable Battery Charger Circuit Using Lm317 1f3t1f

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

ELECTRONICS HUB P R OJ E C T S | T U TO R I A L S | C O U R S E S

HOME

PROJECTS

PROJECT KITS

COURSES

MINI PROJECTS

FREE CIRCUITS

TUTORIALS

SYMBOLS

DIY

US

HOME » DIY PROJECTS » HOW TO MAKE AUTOMATIC BATTERY CHARGER?

How To Make Automatic Battery Charger? FEBRUARY 1, 2016 BY — 38 COMMENTS

Contents [hide] 1 Automatic 12v Battery Charger Circuit Diagram 1.1 Output Video: 1.2 Circuit Principle 1.3 Charger settings 2 2.Automatic Battery Charger 2.1 Circuit Diagram 3  3.Battery charger Using SCR 4 Related Articles

http://www.electronicshub.org/automatic-battery-charger-circuit/

1/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

Have you ever tried to design a battery charger which charges the battery automatically when battery voltage is below the speci ed voltage? This article explains you how to design an automatic battery charger. Below charger automatically shut o the charging process when battery attains full charge. This prevents the deep charge of the battery. If the battery voltage is below the 12V, then circuit automatically charges the battery.

Automatic 12v Battery Charger Circuit Diagram

http://www.electronicshub.org/automatic-battery-charger-circuit/

2/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

Circuit Diagram of Automatic Battery Charger

This automatic battery charger circuit is mainly involves two sections – power supply section and load comparison section. The main supply voltage 230V, 50Hz is connected to the primary winding of the center tapped transformer to step down the voltage to 15-0-15V. The output of the transformer is connected to the Diodes D1, D2. Here diodes D1, D2 are used to convert low AC voltage to pulsating DC voltage. This process is also called as recti cation. The pulsating DC voltage is applied to the 470uF capacitor to remove the AC ripples. Thus the output of the capacitor unregulated Dc voltage. This unregulated DC voltage is now applied to the LM317 variable voltage regulator to provide regulated DC voltage. The output voltage of this voltage regulator is variable from 1.2V to 37V and the maximum output current from this IC is 1.5A. The output voltage of this voltage regulator is varied by varying the pot 10k which is connected to the adjust pin of LM317. [Also Read: How To Make an Adjustable Timer ] Lm317 voltage regulator output is applied to the battery through the diode D5 and resistor R5. Here diode D5 is used to avoid the discharge of battery when main supply fails. When battery charges fully, the zener diode D6 which connected in reverse bias conducts. Now base of BD139 NPN transistor gets the current through the zener so that the total current is grounded. In this circuit green LED is used for indicating the charge of the battery. Resistor R3 is used to protect the green LED from high voltages. http://www.electronicshub.org/automatic-battery-charger-circuit/

3/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

Output Video:

Circuit Principle If the battery voltage is below 12V, then the current from LM317 IC ows through the resistor R5 and diode D5 to the battery. At this time zener diode D6 will not conduct because battery takes all the current for charging. When the battery voltage rises to 13.5V, the current ow to the battery stops and zener diode gets the su cient breakdown voltage and it allows the current through it. Now the base of the transistor gets the su cient current to turn on so that the output current from LM317 voltage regulator is grounded through the transistor Q1. As a result Red LED indicates the full of charge.

Charger settings The output voltage of the battery charger should be less than 1.5 times of the battery and the current of the charger should be 10% of the battery current. Battery charger should have over voltage protection, short circuit protection and reversed polarity protection.

“

NOTE: Also get an idea about how to build a battery charging level indicator circuit?

2.Automatic Battery Charger

http://www.electronicshub.org/automatic-battery-charger-circuit/

4/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

2.Automatic Battery Charger Circuit Diagram

An Automatic Battery Charger Circuit for sealed lead acid batteries is mentioned in this project. It is a pulsed-charger type circuit which helps in increasing the life of batteries. The working of this circuit is explained below. LM317 acts as voltage regulator and current controlling device. The 15V Zener diode is used to set the LM317 to supply 16.2V at output in the absence of load. When the 2N4401 is turned ON by the output of 555, the ADJ pin of the LM317 is grounded and its output voltage is 1.3V. LM358 acts as a comparator and voltage follower. LM336 is used to supply a reference voltage of 2.5V to non-inverting terminal (Pin 3) of LM358. A voltage divider network is used to supply a portion of battery’s voltage to inverting terminal (Pin 2) of LM358. When the charge in the battery reaches 14.5V, the input to inverting terminal of LM358 is slightly greater than 2.5V at Pin 3 set by LM336. This will make the output of 555 go high. http://www.electronicshub.org/automatic-battery-charger-circuit/

5/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

As a result Red LED glows and the transistor is turned on. This will ground the ADJ pin of LM317 and its output falls to 1.3V.

When the charge in the battery falls below 13.8V, the output of LM358 is high and the output of 555 is low. As a result, voltage ows from LM317 to battery and Green LED glows to indicate charging. [Related Post– Lead Acid Battery Charger using LM317]

 3.Battery charger Using SCR

http://www.electronicshub.org/automatic-battery-charger-circuit/

6/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

An automatic battery charger circuit using SCR is implemented in this project. It can be used to charge 12V batteries. Batteries with di erent potentials like 6V and 9V can also be charged by choosing appropriate components. The working of the circuit is as follows. The AC supply is converted to 15V DC with the help of transformer and bridge recti er and the Green LED is turned on. The DC output is a pulsating DC as there is no lter after the recti er. This is important as SCR stops conducting only when the supply voltage is 0 or disconnected from supply and it is possible only with pulsating DC. Initially, SCR1 starts conducting as it receives a Gate voltage via R2 and D5. When SCR1 is conducting, 15V DC will ow through the battery and the battery starts to charge. When the charge on the battery is almost full, it opposes the ow of current and the current starts to ow via R5. This is ltered with C1 and when the potential reaches 6.8V, Zener ZD1 starts conducting and supplies enough Gate voltage to SCR2 to turn it on. As a result, the current ows through SCR2 via R2 and SCR1 is turned o as both gate voltage and supply voltage are cut o . The Red LED is turned on indicating a full charge on the battery.

http://www.electronicshub.org/automatic-battery-charger-circuit/

7/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

Know how to design a circuit of auto cut-o and auto charging of a battery  using SCR.

Related Articles

Variable Power Supply

How To Make Automatic

How To Make A DC

12V DC to 220V AC

Circuits

Night Lamp?

Adapter From Car

Converter [Tested

Battery (Tested)

Circuit]

Car Battery Charger

Working of Full Wave

Voltage Doubler and

How To Make Portable

Circuit

Recti er

Voltage Tripler Circuits

Battery Charger?

http://www.electronicshub.org/automatic-battery-charger-circuit/

8/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

FILED UNDER: DIY PROJECTS

Comments

ranjit says AUGUST 17, 2014 AT 8:41 PM

hi, i want to charge nokia bl-5c battery. i am using the same component, with accordingly adjusted values. my output is 5.22v, and 1.5 amp of current. if i will put my battery in charge forever with my application. then will there be any problem for explosion of the battery, and in that case what should be the value of the diode D6. thanks in advance please reply urgently Reply

n dowidar says DECEMBER 23, 2015 AT 1:04 PM

Hi to charge a 5 volt batt. All what you need is to change the circuit to 5 volt output and it come on di erent circuit. Your goal at that time is to maintain lower temperature

http://www.electronicshub.org/automatic-battery-charger-circuit/

9/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

which will not damage yr. Batt. So di erent circuit is recommended. Reply

bala appu says FEBRUARY 1, 2016 AT 7:18 AM

1.5 amps for ur li-ion battery was very high. all u have to do is to reduce the current. according to ur circuit u dont want to worry about the voltage. becoz 5.22 v is safe to charge. just try to place a resistor before load to limit the current. each and every battery has there own initial current value (charging current) u have to charge according to that unless u battery may explode. Reply

Leon says AUGUST 30, 2014 AT 7:06 AM

“This circuit is tested in simulation software and may require some practical changes.” Did someone build this charger & does it work OK? Reply

n dowidar says DECEMBER 23, 2015 AT 12:59 PM

Yes i did and work very good, no trouble at all. Reply

Chirag says http://www.electronicshub.org/automatic-battery-charger-circuit/

10/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

NOVEMBER 8, 2016 AT 8:58 AM

did u simulate sir? and what software did u use? Reply

bishow kandel says SEPTEMBER 22, 2014 AT 12:22 PM

hey dude concept of circuit is cool but i think value of zener diode is less so breakdown early while switching on circuit can u please help me with your view my email address is [email protected] Reply

Zydon says OCTOBER 21, 2014 AT 7:13 AM

Hey. I have built your battery charger above but it did not work as it should for some reason. The green LED is constantly ON and the red LED is acting the same… Reply

rdaus says NOVEMBER 28, 2014 AT 10:36 AM

can this circuit use to charge mobile phone through usb? Reply

http://www.electronicshub.org/automatic-battery-charger-circuit/

11/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

n dowidar says DECEMBER 23, 2015 AT 1:05 PM

No no no Reply

Romania says JANUARY 6, 2016 AT 11:06 AM

Yes, but you need a new phone after. Reply

Sajjad says JUNE 11, 2017 AT 2:01 AM

Allah

what ghylreat idea…

Reply

Mrunal Ahirrao says NOVEMBER 26, 2015 AT 5:08 AM

Nice circuit! thanks for sharing Reply

http://www.electronicshub.org/automatic-battery-charger-circuit/

12/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

ashmin bhandari says JANUARY 5, 2016 AT 7:24 AM

i want to know…why in this charger uses lm317 voltage regulator …why other not..is it possible if iam using another voltage regulator..plz reply me Reply

Anusha says JANUARY 30, 2016 AT 6:43 AM

we are charging a 12 v battery here..so the output voltage should be between 1416v..for that reason we have used LM317 Reply

MINARUL says JANUARY 30, 2016 AT 1:38 AM

I WANT TO USE THIS CIRCUIT FOR 10W20V SOLAR , I MEAN I WANT TO RECHARGE MY 12V9AH BATTERY BY USING SOLAR ! IS IT POSSIBLE? Reply

anwar says JANUARY 30, 2016 AT 2:18 AM

In the scehmatics of LM317 based 1st Project, I am not able to locate POT, its connections and its value. I have noticed it only in video. Pleas help! Reply

http://www.electronicshub.org/automatic-battery-charger-circuit/

13/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

Anusha says JANUARY 30, 2016 AT 8:00 AM

Please check below Lm317 IC ,there is 10k POT Reply

Prithwiraj Bose says JUNE 29, 2016 AT 12:37 AM

I couldn’t get the POT working – the voltage control never worked. I always get around (Vin – 1.25) volts. Something seems wrong in the circuit. Reply

ranjithmendis says FEBRUARY 10, 2016 AT 1:12 PM

I want high frequecy inverter circuit diagram Reply

moaz mohamed says FEBRUARY 11, 2016 AT 7:19 AM

can i modify one of these circuits to charge a laptop lets apples laptop ? Reply

Anusha says http://www.electronicshub.org/automatic-battery-charger-circuit/

14/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

FEBRUARY 15, 2016 AT 8:20 AM

Laptop battery need around 18-21 V at 3 to 4A. So these circuits would not be very useful. Laptop charging circuit can be designed using XL6009. Reply

AUSTINE KAUZENI says FEBRUARY 20, 2016 AT 12:10 AM

Hello brothers i got a question,my name is Austine from Tanzania i need to create an inverter thag can charge itself but i have no idea on how to make it becouse i have no circuit diagram of inverter, Charging system,Delay timer for switching on AC output, And battery voltage drop indicator/battery monitor Reply

Imran says MARCH 6, 2016 AT 10:32 AM

I made this circuit but it is giving max 8 v output What should i do Reply

Dalton Rabon says MARCH 22, 2016 AT 12:45 PM

Hi , I am just curious to know if this could be used to charge 2 12 volt slap batteries in series with the input voltage coming from the pedaling of a bicycle connected to a motor with the polarities reversed in order to create voltage. Would this be able to work if my input voltage to the circuit was a varying DC voltage? http://www.electronicshub.org/automatic-battery-charger-circuit/

15/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

Any help would be appreciated . I am trying to design a circuit to charge (2) 12 volt 10aH sla batteries using the power from bicycle pedaling, Reply

Murali says APRIL 8, 2016 AT 12:01 AM

In the battery charger Using SCR circuit above, wanted to clarify regarding the maximum current which would through SCR1. Assuming we are connecting a discharged Lead Acid battery. Then when the circuit is powered ON, the peak AC voltage at the anode of the SCR1 would be 21V (15V rms). This would forward bias the SCR1 since cathode is at zero voltage (as battery output is zero). The Gate of SCR1 is at higher potential than Cathode and hence SCR1 would conduct. At this stage since the internal resistance of a battery is in the range of 20-50 milli ohm. The current which would through SCR and battery as per Ohm’s law would be approx. 20V/20 milli ohm (assuming 1V drop across SCR in conduction phase). This would be a very large current which could potentially damage the SCR/battery. Is there something I am missing here? Reply

amir says APRIL 9, 2016 AT 12:28 PM

Hi Is there any way to change the minimum and maximum voltage of Battry??? Plz help me Reply

gin says APRIL 10, 2016 AT 9:55 PM

http://www.electronicshub.org/automatic-battery-charger-circuit/

16/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

pls help i want to use 6v battery what will i do Reply

zeeshan says APRIL 11, 2016 AT 11:06 PM

hi guys! can anybody suggest me that may I use this charger ckt in order to charge a battery of NI-MH 9.6 v of power bank.. Reply

Akhil says MAY 1, 2016 AT 10:56 AM

Can I use 12-0-12 transformer?? Reply

Ezequiel says MAY 3, 2016 AT 11:34 AM

So this charger cuts the charging process until the battery discharges again or it stays charging the battery all the time to avoid several charge/discharge process? Reply

Aaryan says MAY 8, 2016 AT 4:00 PM

http://www.electronicshub.org/automatic-battery-charger-circuit/

17/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

I have connected everything correctly. However when I am connecting the battery green light is glowing and also both led is getting on when I am giving the power supply. The output voltage is getting xed to 8.9 however the lm 317 output voltage ig 22.1 Volt. please check and help me with correct circuit and components. Thanks Reply

Oguz Coskun says MAY 14, 2016 AT 6:28 AM

Hello, Thank you very much for sharing such knowledge. I have tried cut-o with SCR but I have used BUT12A instead os SCR. I also added Regulator with 7805 to the input of the Charger Using SCR circuit. Now the 10K adjust the voltage very well but without SCR the red LED only turns o when it is higher than 13 V. I always use components from old electronic devices. I will try to charge my 12V battery from my wind tribune I have build with used electronic devices’ components. Thank you for your time and interest. Reply

Oguz Coskun says JUNE 17, 2016 AT 7:54 AM

I added a 4N35 to control the charge of my battery when there is no power from the wind and the sun. I can send you the circuit. Thank you very much for such circuit giving me the chance to build my charge control. Reply

http://www.electronicshub.org/automatic-battery-charger-circuit/

18/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

James Lam says MAY 18, 2016 AT 12:07 PM

This battery charger is safety or not? And what is the function of the POT in the “Battery Charger Circuit using SCR”? Please reply urgently, thank you, Reply

Prithwiraj Bose says JUNE 28, 2016 AT 3:11 PM

Ah! I nally made the BD139 based circuit and as expected – IT DIDN’T WORK. The Pot did nothing to regulate the output voltage. Infact there is no way to regulate and measure the output voltage properly at ‘no load’ condition. Reply

terry-romeo says AUGUST 4, 2016 AT 7:13 AM

Hellow brother,can i use the circuit above to charge twelve volt battery and to supply my simple tra c light control system using timer and 4017 counter ic???? Reply

ABDULLAH AL MAMUN says MARCH 8, 2017 AT 11:15 PM

this website help me to 12 volt auto cut relly…..many thanks Reply

http://www.electronicshub.org/automatic-battery-charger-circuit/

19/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

Leave a Reply Your email address will not be published. Required elds are marked * Comment

Name *

Email *

Website

  POST COMMENT

Search this website …

http://www.electronicshub.org/automatic-battery-charger-circuit/

20/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

Suggest A Topic [or] Project

COMPLETE STEP BY STEP GUIDE

http://www.electronicshub.org/automatic-battery-charger-circuit/

21/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

SUBSCRIBE FOR FREE PROJECT CIRCUITS

Enter your email address:

SUBSCRIBE

Delivered by FeedBurner

http://www.electronicshub.org/automatic-battery-charger-circuit/

22/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

PROJECTS BY CATEGORY

http://www.electronicshub.org/automatic-battery-charger-circuit/

23/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

Arduino Projects (200+) Electronics Projects (250+) Mini Project Circuits (160+) Mini Project Ideas (150+) ECE Projects (150+) EEE Projects (150+) 8051 Projects (110+) Raspberry Pi Projects (101+) Electrical Project Ideas (100+) Embedded Projects (100+) Latest Electronics Ideas (100+) Microcontroller Mini Projects (100+) Robotics Projects (100+) VLSI Projects (100+) Solar Projects (100+) IOT Projects (100+) Communication Projects (70+) LED Projects (70+) Power Electronics Projects (60+) RFID Projects (60+) Home Automation Projects (50+) Matlab Projects (50+) EIE Projects (50+) Wireless Projects (50+) LabView Projects (45+) Zigbee Projects (45+) GSM Projects (40+) 555 Timer Circuits (40+) Sensor Projects (40+) ARM Projects (60+) DTMF Projects (30+) PIC Projects (30+) Electrical Mini Projects (25)

GENERAL

PROJECTS

PROJECTS

Tutorials

Electrical

Mini projects

Symbols

Electronics

Microcontroller

http://www.electronicshub.org/automatic-battery-charger-circuit/

24/25

8/29/2017

Automatic 12v Portable Battery Charger Circuit using LM317

Courses

Embedded

Aurdino

Calculator

Power

Solar



Robotics

Free circuits

ARM

Home Automation

IOT TUTORIALS

Capcitors Resitors Filters Diodes Transistors TUTORIALS

FOLLOW US

Ampli ers

Facebook

IO Devices

Youtube

Thyristors

Google Plus

DC Circuits

Twitter

Nummber System

Copyright © 2017 Electronicshub.org

http://www.electronicshub.org/automatic-battery-charger-circuit/

25/25