Buy sodium-ion batteries (salt batteries) inexpensively

Advantages of sodium-ion batteries

Availability of raw materials: Sodium is abundant on Earth and widely available, unlike lithium. It occurs in large quantities in seawater and various minerals, which reduces dependence on geopolitically unstable regions.
Environmental friendliness: The extraction of lithium is often associated with significant environmental impacts, including water consumption and soil degradation. Sodium-based materials can be mined and processed in a more environmentally friendly way.
Thermal stability: Sodium-ion batteries tend to have much better thermal stability than lithium-ion batteries. There is no risk of overheating and fires! This is particularly important for applications where safety is a major concern - especially for boats that are difficult to extinguish.

Disadvantages of sodium-ion batteries

Lower energy density: One major disadvantage of sodium-ion batteries is their slightly lower energy density compared to lithium iron phosphate batteries. LiFePO4 has around 210 Wh/kg and SIB has around 160 Wh/kg. This means that NIBs are less attractive in applications that require high energy density, such as electric vehicles.
Larger and heavier cells: Sodium-ion batteries are larger and heavier than lithium-ion batteries, which can lead to heavier and larger battery packs. This could be problematic in applications where weight and space are critical factors.

Functioning of salt batteries

Sodium-ion batteries work on a similar principle to lithium-ion batteries. However, the fundamental difference is that sodium ions (Na⁺) are used as charge carriers instead of lithium ions (Li⁺). The main components of a sodium-ion battery are:

Cathode: The cathode is made of sodium cobalt oxide (NaCoO2), which absorbs Na⁺ ions during discharge and releases them during charging.

Anode: Hard carbons, soft carbons, or metal oxides are typically used as anodes. In our case, we use carbon.

Electrolyte: The electrolyte typically consists of a sodium salt solution dissolved in an organic solvent. It serves as the medium through which the sodium ions migrate between the anode and cathode during charging and discharging.

Separator: The separator is a microporous membrane that separates the anode and cathode while allowing the flow of Na⁺ ions.

Charging and discharging process

Charging: During the charging process, sodium ions are extracted from the cathode and transported through the electrolyte to the anode, where they are embedded in the anode structure.

Discharging: During discharging, the Na⁺ ions are released from the anode, migrate through the electrolyte back to the cathode, and generate an electron flow through the external circuit, which provides electrical energy.

Conclusion on salt batteries

Sodium-ion batteries are a promising alternative to lithium-ion batteries, especially in terms of sustainability and safety. However, their lower energy density currently limits their applications - at least for electric cars. On the other hand, salt batteries can already be used for boats.