Bio Battery: Construction, Working, Advantages, and Disadvantages

This tutorial covers the basics of bio batteries, including their construction, working principles, advantages, disadvantages, and different types.

Bio Battery Construction

Figure 1 depicts the construction of a bio battery. As shown, it consists of an anode, cathode, electrolyte, and separator, layered on top of each other.

• Anode: The negative terminal, located on top of the battery.
• Cathode: The positive terminal, located on the bottom. Electrons enter the battery from the anode, and current flows out from the cathode.
• Electrolyte: Present between the anode and cathode, facilitating ion transport.
• Separator: Keeps the anode and cathode separate to prevent short circuits.

Unlike conventional batteries, bio batteries utilize biological enzymes as catalysts at the anode and cathode. These enzymes and electronic mediators are fixed on both terminals.

Bio Battery Working

Figure 2 illustrates the working principle of a bio battery. The system is designed to allow the flow of both electrons and protons, generating electricity. The movement of protons, driven by a moving force, constitutes an electric current. Electrons flow from the anode to the cathode, while the conventional current flows from the cathode to the anode.

Here’s a step-by-step breakdown:

1. Glucose and Enzyme: Glucose is used on the anode side, while an enzyme is present on the cathode side.
2. Glucose Breakdown: Glucose is broken down into protons ($H^+$) and electrons ($e^-$).
3. Proton and Electron Transport: Protons move to the cathode side through the separator, and electrons move to the cathode side through a mediator.
4. Water Production: Enzymes at the cathode utilize both electrons and protons to produce water, employing an oxygen reduction reaction. $O_2 + 4H^+ + 4e^- \rightarrow 2H_2O$
5. Energy Generation: The reactions create electrons ($e^-$) and protons ($H^+$) in the system, resulting in the generation of electrical energy.

Types of Bio Batteries

Based on the agents involved in the breakdown of the substrate, which produces protons and electrons to generate electricity, there are two main types:

• Enzymatic Bio-Battery: Utilizes enzymes (biochemical agents) to break down the substrate.
• Microbial Bio-Battery: Employs microorganisms (electric bacteria, Escherichia coli, etc.) to break down the substrate.

Other types include cellulose-based bio batteries and body fluid-based bio batteries.

Bio Battery Advantages

• Instant Recharge: Allows for instant recharge compared to other batteries.
• Self-Charging: Maintains charge with a continuous supply of glucose or sugar, eliminating the need for external power.
• Readily Available Fuel: Can be made using readily available fuels.
• High Energy Density: Offers a high energy density.
• Room Temperature Operation: Can be easily used at room temperature.
• Flexible and Implantable: Flexible paper prototypes can be used as implantable power sources.
• Clean and Renewable: Serves as a clean, alternate, and renewable power source due to the use of non-toxic and non-flammable fuels.
• Safe: Does not cause explosions and is safe to use.
• Leak-Proof: Does not cause leakage.

Bio Battery Disadvantages

• Lower Energy Retention: Less likely to retain most of their energy compared to conventional batteries like lithium-based batteries.
• Short Lifespan: Not suitable for long-term usage and storage.

Bio Battery Applications

• Portable Charging: Used in cell phones, soldier power applications, etc.
• Medical Implants: Used in medical implants such as pacemakers and insulin pumps.
• Disaster Relief: Used in generators and remote power solutions.
• Toys and Greeting Cards: Utilized in toys and greeting cards.

This bio battery tutorial is intended to be useful for both beginners and advanced enthusiasts.