Chemistry & Cell Components

Chemistry & Cell Components

Active

Cathodes

Anodes

Inactive

Sodium Ion | Materials Selection

Material Properties

Capacity (mAh/g)

Voltage Range (V)

Tap Density (g/cm3)

Cycle Life

Safety

Layered Oxide

Releases heat + O2 during TR

Polyanion

Limited heat release

Prussian Blue/White

Releases cyanide gas during TR

Hard Carbon

Releases energy rapidly, burns to CO2

Alloys

Releases energy slowly, oxidizes to M-O2

Sodium / Anodeless

4.2V in NVPF *

Material Properties

Description

Prospects & Challenges

Thermal safety still unproven Wide voltage range limits integration

Poor volumetric energy due to tap density Limited rate capability / power density

High moisture sensitivity leads to higher costs Poor volumetric energy due to tap density

Poor volumetric energy due to tap density

Feedstock limits costs & quality

Need to manage high volume change

Limited cycle life reported

Na foil processing challenges Na-free cycle life limitations & volume change

Prospects & Challenges

Ether based

NaPF6 salt in Linear Glymes

Ethers are compatible with Na anodes (incompatible with graphite), offers superior SEI stability Limited oxidative stability, cannot be used with high voltage cathodes

Carbonate based

NaPF6 salt in Cyclic/Linear carbonate mixtures

Good oxidative stability, but need to manage gas generation/accumulation at high voltage Not compatible with metal-based anodes

Aluminum Foil

Used at both Anode and Cathode

Aluminum does not react with sodium (unlike lithium), Use on both electrodes reduces weight, cost and critical material needs of copper

Electrolyte

Current Collector

Sodium Ion | Materials Selection

Extracted from the PDF; charts and images may read imperfectly.