Solar Assisted Battery Charging System with Active Cell Balancing Mechanism
Battery cell balancing is an important feature for the long-term survival of the batteries because unbalancing of battery cell may cause the deterioration of the battery life cycle and efficiency. Moreover, it can damage the electrical equipment. The aim of the project is to design an intelligent ba
2025-06-28 16:36:01 - Adil Khan
Solar Assisted Battery Charging System with Active Cell Balancing Mechanism
Project Area of Specialization Electrical/Electronic EngineeringProject SummaryBattery cell balancing is an important feature for the long-term survival of the batteries because unbalancing of battery cell may cause the deterioration of the battery life cycle and efficiency. Moreover, it can damage the electrical equipment. The aim of the project is to design an intelligent battery management system that will have the capability to balance the unbalance cells, which can increase the life span of the weak cell and can increase the overall battery capacity and charging cycles. The idea behind developing active cell balancing mechanism is to observe the state-of-charge (SoC) of Lithium-ion cells in the battery pack and apply an extra storage cell in parallel to the battery cell that is weak at any certain time. The energy is transferred between the extra storage battery and the Lithium-ion battery to balance the Li-ion cells. By adjusting the duration of time at which the extra storage cell and main battery pack are connected in parallel, thus purpose of battery equalization will be achieved. The battery cell balancing system can minimize voltage difference between the battery cells to match the SoC levels.
In this project, a solar power assisted battery charging system is proposed with active cell balancing mechanism. The analysis includes the case study of battery cells balancing system. There are three operation modes discuss in the project: (a) solar-balancing mode, (b) storage-balancing mode, and (c) charge-balancing mode. In solar-balancing mode, the battery will be charged using the solar power. For this purpose, a charge controller will be implemented. When there is no load, then charge-balancing mode is activated. In charge-balancing mode, the battery cells are charged by plugin the conventional charger and discharges the battery cells with highest SoC to storage cell. When the solar power is not available, the storage-balancing mode will be operated to charge the battery cells with low SoC using energy stored in storage cell. The system will have the capability to minimize the energy loss that could happen in conventional active and passive balancing techniques in form of heat dissipation across resistance or inductors.
Project Objectives-
Design a simulation setup for solar assisted battery cell charging and cell balancing system.
- Design and implementation of solar assisted charge controller in hardware setup for lithium-ion battery.
- A real-time health monitoring system will be design for lithium-ion cells by observing and measuring parameters, such as voltages, current, temperature, and SOC.
- Design and implementation of battery cell balancing circuit.
The project proposes a solar power assisted Li-ion battery charging system with active cell balancing method. Based on active cell balancing technique, energy of Li-ion cells of a battery pack is transferred to extra storage cell connected in parallel through DC-DC buck-boost converter to balance cell voltages. There are control switches connected to each Li-ion cells of the battery pack. A controller will be designed to detect the imbalance of cell voltages and allows the switches to transfer Li-ion cell voltages to the extra storage cell. Therefore, the excess charges from high voltage are pumped into the inductor and discharges the voltages into the extra storage cell, thus purpose of battery cell balancing will be achieved. It is worth noticing that the discharge energy from Li-ion cells is not wasted rather it is stored in the extra storage cell. Therefore, the stored energy can be re-utilized to charge the Li-ion cells. 
- Active cell balancing system is utilized in battery management system to increase the life of batteries.
- The project finds its application in hybrid electric vehicle (HEV’s) to increase the performance of the Li-ion batteries.
- In Pakistan, there is an essential need of an efficient battery cell balancing system for UPS systems in the residential sector. Moreover, current involvement of roof-top micro solar power generation also required to have an effective cell balancing system to storage the excess energy in the batteries that can be sold to the national grid utilizing net-metering technique.
- The cell balancing system is used in industries with integrated battery-based storage system for developing highly automated power system.
- In active cell balancing system, the discharge energy from Li-ion cells is not wasted rather it is stored in the extra storage cell. Therefore, the proposed system is energy efficient and have the capability to re-utilize the stored charge in the Li-ion cells of the battery pack.
Final deliverable of the project is a hardware setup that will have the capability to charge the battery on solar power, while manage the battery cells with active cell balancing mechanism. Hardware system consisting of solar panel having wattage of 150W will be used to charge the 12V lithium-ion battery through PWM charge controller. Battery health monitoring circuit will be integrated to continuously measure the cell voltages of Li-ion battery. Another controller will be designed to detect the balance/imbalance condition and to control the switch box for taking action for battery cells voltage balancing. The extra storage cell is connected parallel to the Li-ion battery through DC-DC buck boost converter to transfer voltages between extra storage cell and Li-ion battery. Solar panel, Li-ion battery, DC-DC converter, and extra storage cell is interlinked through the same DC bus bar and all the connections will be controlled by the switching box.
Final Deliverable of the Project Hardware SystemCore Industry EducationOther Industries Energy , Transportation Core Technology OthersOther Technologies OthersSustainable Development Goals Affordable and Clean EnergyRequired Resources| Item Name | Type | No. of Units | Per Unit Cost (in Rs) | Total (in Rs) |
|---|---|---|---|---|
| Total in (Rs) | 79800 | |||
| Solar Panel 300W | Equipment | 1 | 15000 | 15000 |
| Charge Controller (PWM) | Equipment | 1 | 6000 | 6000 |
| Dry Battery 12V/18Ah | Equipment | 1 | 5000 | 5000 |
| Lithium-ion Cells 4V | Equipment | 25 | 420 | 10500 |
| Health Monitoring Device (ISDT Batt Go) | Equipment | 2 | 7500 | 15000 |
| Controller (Arduino Mega) | Equipment | 1 | 2000 | 2000 |
| Voltage Sensor | Equipment | 1 | 4000 | 4000 |
| Current Sensor | Equipment | 1 | 5000 | 5000 |
| Consumable Electronic Items (Capacitors, Inductors, Diodes, wires, con | Equipment | 1 | 2000 | 2000 |
| LCD | Equipment | 2 | 700 | 1400 |
| 12C Module | Equipment | 2 | 350 | 700 |
| Digital Multimeter | Equipment | 1 | 2000 | 2000 |
| Vero Board | Equipment | 5 | 80 | 400 |
| Soldiering Kit | Equipment | 1 | 800 | 800 |
| Overheads | Miscellaneous | 1 | 4000 | 4000 |
| Printing | Miscellaneous | 1 | 3000 | 3000 |
| Stationery | Miscellaneous | 1 | 3000 | 3000 |