What Is A Lithium Thionyl Chloride Battery?

A **lithium thionyl chloride (Li-SOCl₂) battery** is a type of non-rechargeable (primary) lithium battery. It uses lithium metal as the anode and **thionyl chloride (SOCl₂)** as the cathode and electrolyte. These batteries are known for their **high energy density**, **long shelf life**, and **wide operating temperature range**, making them well-suited for applications requiring reliable, long-lasting power sources.

Key Features:

1. **High Energy Density**: These batteries have one of the highest energy densities among primary batteries, providing more power per unit weight and volume.

2. **Wide Temperature Range**: Lithium thionyl chloride batteries can operate effectively in extreme temperatures, from around **-55°C to +150°C**, making them suitable for environments with fluctuating or extreme temperatures.

3. **Long Shelf Life**: These batteries have a very low self-discharge rate (typically around 1% per year), allowing for **10-20 years of storage** without significant capacity loss.

4. **Applications**: Commonly used in applications where battery replacement is difficult, such as **remote monitoring systems, military equipment, medical devices, utility meters, and GPS tracking systems**.

 Advantages:

- High energy density and voltage (usually around 3.6V per cell).

- Long storage life due to low self-discharge.

- Resistant to temperature extremes.

 Disadvantages:

- They cannot be recharged, so once depleted, they need to be replaced.

- Thionyl chloride is highly reactive and toxic, so these batteries require careful handling and disposal.

Safety Considerations:

Due to the reactivity of lithium and thionyl chloride, these batteries are generally built with safety mechanisms to prevent issues like **leakage, venting, or thermal runaway** in case of a short circuit or mechanical damage.