# 4 Lead acid battery charging circuit using LM317

Here is 4 lead acid battery charging circuit
When you want to build the lead-acid battery charger project for 6V battery or 12V. Although there are many methods to choose from. I like using IC LM317 Because easy to use, with minimal equipment. Cheap and good. Today, I try to collection ideas for the battery charger circuit. This is just part one.

*** Note: Though This project is good but it may difficut to build and expensive. I love this projects better : Simple auto cut off 12V battery charger

There are 4 circuits, as follows.

### 1. The universal battery charger using Lm317

Here comes very simple idea is the universal battery charger circuit.
When, an input power is applied to the circuit.
The SCR1 (Silicon controlled rectifier) turn off, then not has a bias current path to ground.

The LM317 acts as a current regulator, It is connected to the battery thought a one way diode D1, limiting resistor R1, and a bias resistor R2.
The D1 prevents the circuit from battery discharging, when the power out off from this circuit.
As the battery charges, the voltage across A point potentiometer R5 and some point rises, to turn on the SCR1.
Then current from the regulator LM317 can flow to ground, so now the IC1 is in functions the voltage-regulating mode.
The R6 be used to control the output voltage.
When the SCR1 turn on, it also provides LED1 through R3 with a path to ground.
But when LED1 is on, this circuit is in the voltage-regulating mode, while LED1 is off to be in the current-regulating mode.

### 2. 6V or 12V lead acid battery charger using LM317

This circuit be lead acid battery charger again interesting circuit, Because it can charger get both of 12V sizes and 6V. By change with switch only and this circuit charging with current about 1Amp. When see the circuit you will think us uses integrated number highly popular circuit be LM317K again. By when you Close SW1 make can charger battery 6V get. Which have voltage come out about 7 Volt. But enough Open SW1 as a result use charging battery 12 V get. Which give volt come out about 14Volt supposing that you use battery 6V 10Ah take time charging current 10 long ago hour. The diode D3 and D4 help protect voltage turn back from battery get. The detail is other see in the circuit.

Note: Or you can use this : Automatic Battery Charger 6V-12V with Relay cut off by LM324 as well.

### 3. 12V lead acid battery charger by LM317K

Today a close friend visits tell want Dry cell lead acid battery charger circuit 12V 7.5hA sizes. In model to are simple and economize with. I then advise this circuit try build see. By use the integrated circuit voltage regulator the number is highly popular be , LM317K. This circuit has the principle is simple be heal level voltage be stable 13.5 Volt. Because battery must use voltage tall more then charger get follow want.

Which battery of a friend must use current 1A take time charging about 8 hour then will have the electric energy with full speed ahead. The detail is other ,

### 4. Automatic Charger and Full charged indicator using LM317K-TL431

This is circuit Automatic Charger and Full charged indicator. For 24V batteries it can charger with current be stable about 1.5A and have voltage output 27Volt with integrated number circuit LM317K. When the battery has had full already , as a result will cut the work. There is a tube LED show the work with use integrated number circuit LT431 perform check the level , voltage battery and systematically protect short circuit with IC LM317. Unless D2 perform protect wasp a pole battery wrong as well. The IC1 should hold heat sink with. The detail is other , see in the circuit.

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