Optimal Charge controller for Lead acid and Lithium ion batteries

Project Title

Optimal Charge controller for Lead acid and Lithium ion batteries

Project Area of Specialization Electrical/Electronic EngineeringProject Summary

A charge controller is an essential part of nearly all power systems that charge batteries, whether the power source are solar panels, wind, hydro, fuel, or the utility grid. Its purpose is to keep your deep cycle batteries properly fed and safe for the long term.

The basic functions of a controller are quite simple. Charge controllers block reverse current and prevent battery overcharge.

 Some controllers also prevent battery over discharge, protect from electrical overload, and/or display battery status and the flow of power.

Different type of batteries use different charge controllers Lead Acid batteries would have different charge controllers then Lithium-ion batteries as they have different charging methods.

 Lithium ion batteries are preferable then Lead Acid Batteries as the have more charge density and more power output capacity acquiring less space then Led Acid batteries and have greater importance in EV and PV system.

Our charge controller is not only going to able to charge batteries with efficiently, but it will also enable us to charge two different type of batteries with same controller. Moreover providing safety while charging and real time monitoring of battery temperature will be a feature of our charge controller as well.

Project Objectives

Objectives

1. In this project charging Both Lead Acid and Lithium ion batteries through a single charge controller with optimum efficiency and depth charging is key objective. 
2. Charging both batteries Effecttively in less time.
3. Helping Consumers by providing user friendly structure so it can be operate by any person with ease.
4. Discharge current protection will be given to batteries.
5. Over Voltage protection will be given to battery.
6. Over Charge protection will be given to batttery.

Project Implementation Method

Implementation:

Our project has basically two parts:

• Supply Part
• Controller Part

• Supply Part:

In supply part we convert alternating current and voltages into direct current and voltage and we get variable currents and voltages for different levels of charging in batteries.

• Controller Part:

In controller part we get inputs from the user and select the charging mode based on input. After selecting the charging method controller controls the current and voltages from supply for different charging levels.

Benefits of the Project

Benefits

The Project Benefits are as follows

1. Charging multiples batteries types with a single charger keeping in view that both Lead Acid and Lithium ion batteries have different charging  mechanisms.
2. Our charge controller is not only going to able to charge batteries with efficiently, but it will also enable us to charge two different type of batteries with same controller.
3. Consumer will be able to use it easily as it has user friendly system and structure.
4. Charger controller for different chargers will not be an option now as our charge controller will charge different batteries having different charging characteristics.
5. Temperature real time monitoring will ensure the safety of battery.
6. Protection from Discharge current will help the user to ensure the battery safety as well as it will help increase the life span of battery.

• Discharge current protection is required to prevent damage or explosion because of short circuits. There will be a limit for the battery pack, and this should not be exceeded. In view of the huge amounts of power stored, exceeding the limits can result in fire or even an impressive explosion.

1. Over Voltage protection will benefit the battery.

• Charge over-voltage protection is required to prevent a voltage that is too high being applied across the battery terminals. if the charge voltage can rise too high then damage can be caused.

1. Over charge protection will help to ensure the safety of battery cells

• The over-charge protection circuitry is required to stop the Li-ion charging process when voltage per cell rises above 4.30 volts. It is extremely important not to overcharge the lithium in battery. The battery management system must provide protection against overcharging.

Technical Details of Final Deliverable

As stated in implementation we have divided our project into 2 parts 

• Control circuit
• Power supply circuit

In power supply circuit I am going to use first a fuse to protect the circuit then after that I am using a Transformer to step down the voltage level that will step down 220v to 12 v. After that I am using a capacitor for filtration, I am using  IC lM723 and then using a 5.3k resistor to pull down the pin 1 of the IC. Similarly to pin 5 &6 are also pull down using a Resistor off 22k ohm. 12 pin is attached to 2 FETS having common base . These transistors are use to vary voltage and current. 2 Diodes are also use to block reverse current for protection . 2 variable resistors are use to vary voltage and current of 10k ohm.

After changing voltage and current to desired battery rating we  connect output to the battery terminals.

In controller circuit we used are using a relay for switching between lithium and lead Acid battery. Using buttons to indicate the control circuit that i.e now we are using Lead Acid battery that my control circuit will give me the desired current and voltage output. In   control circuit in case of over load or short circuit protection we have a feature of switch off feature for safety of the circuit.

Final Deliverable of the Project Hardware SystemCore Industry Energy Other Industries Manufacturing Core Technology OthersOther Technologies Clean TechSustainable Development Goals Affordable and Clean EnergyRequired Resources

Item Name	Type	No. of Units	Per Unit Cost (in Rs)	Total (in Rs)
			Total in (Rs)	43500
12v 8ah lead acid battery	Miscellaneous	9500	1	9500
12v 14ah lithium ion battery	Equipment	34000	1	34000