All solid state battery vs semi solid battery vs liquid battery

Batteries are evolving rapidly. The scientific progress of all solid state battery continues to increase. This article will compare all solid state batteries, semi-solid batteries, and liquid batteries in order to better grasp the most recent advancements in battery technology.

Learn about different battery technologies

Liquid battery

The main materials of liquid batteries are the positive and negative electrodes, the diaphragm and the electrolyte.

Mainly by coating the electrodes with active materials and then immersing the electrodes in the liquid electrolyte, the ions in the electrolyte react with the active materials on the electrodes and release electrons.The famous 18650 lithium battery is also a kind of liquid battery. You can learn more by checking our top 10 18650 battery manufacturers in the world

Semi solid battery

Semi solid lithium batteries are solid-liquid hybrid electrolyte batteries. The positive and negative electrodes, diaphragm, etc. can continue to use the materials of the liquid lithium-ion battery, only the electrolyte adopts the solid-liquid mixture scheme.

All solid state battery

The all solid state battery is a type of battery that uses solid materials for the positive electrode, negative electrode and electrolyte inside the battery, and removes the diaphragm.

Comparison of battery differences-All solid vs semi solid vs liquid

Structural comparison

Liquid battery: electrolyte is one of the key materials in liquid batteries. The electrolyte plays a role in conducting ions between the positive and negative materials inside the battery.

It ensures the effectiveness of the internal circuit and plays a key role in the energy density, power density, cycle life, safety performance, which is called the “blood of the battery”.The technology for the top 10 lithium ion battery electrolyte company in China  is quite mature.

Semi solid battery: retaining part of the electrolyte and diaphragm structure. Semi solid batteries require a small amount of electrolyte to be retained alongside the solid electrolyte to improve conductivity and therefore require a diaphragm to separate the positive and negative electrodes. Depending on the technology, solid electrolytes are also available in granular and membrane form.

All solid state batteriy: No electrolyte retained. Diaphragm need to be studied. In an all solid state battery, the electrolyte will be completely replaced by a solid electrolyte. Whether the diaphragm is replaced or not depends on the different technology routes. In some solid-state battery technology options, the diaphragm is retained as the architecture supporting the electrode; in others, the diaphragm is eliminated altogether.

Comparison of battery materials

Liquid batteries: Liquid batteries consist of four key materials: cathode material, anode material, diaphragm and electrolyte, with cost percentages of 45%, 15%, 18% and 10% respectively. The main component of the liquid electrolyte is an organic solvent that dissolves the lithium salt and provides a carrier for the lithium ions.

Semi-solid batteries: The materials used are essentially the same as those used in liquid batteries. In the case of a semi-solid-state lithium battery, a gel electrolyte is used, using a polymer as the electrolyte “base film” to which lithium salts are added, along with low molecular organic solvents, which are activated by immersion to obtain a substance with an ionic conductivity between that of a solid electrolyte and a liquid electrolyte.

All solid state battery: In the case of all solid state lithium battery, cathode material can continue the lithium-ion battery cathode material, negative electrode material for lithium metal, no diaphragm. Currently, there are four major research areas: lithium sulphide batteries, lithium oxide batteries, lithium oxide batteries, and lithium composite electrolyte batteries.

Manufacturing process comparison

Liquid battery:

The production process of liquid batteries is divided into three stages: pre, middle and post. The purpose of the pre-stage process is to process the raw material into pole pieces, with the core process being coating.

The purpose of the middle stage is to process the pole piece into an inactive cell middle stage process, which mainly includes the winding/stacking of the cell and the liquid injection of the cell. The latter part of the process is the testing and packaging.

Semi solid battery:

The semi-solid state battery preparation process is compatible with traditional lithium battery production processes. The reason why semi-solid-state batteries can be brought to market quickly is that they borrow as much as possible from existing liquid battery equipment and processes, of which only 10%-20% have different process equipment requirements. You can check our top 10 semi solid battery manufacturers in China to learn more.

All solid state battery:

All solid state batteries are somewhat different from traditional ion battery production processes. The electrolyte solution for all solid state battery uses a sol-gel mixture and requires baking to evaporate the solvent and obtain a solid electrolyte film, which requires additional electrolyte coating and UV irradiation and baking processes. As there is no electrolyte, there is no need for a liquid injection process.

Comparison of battery performance

● Energy density

The highest energy density reported commercially for liquid batteries is 300wh/kg.Semi solid batteries is reported 360wh/kg, and the energy density will be further increased through the improvement of cathode and anode materials.The current energy density of all solid state battery is 400wh/kg and is expected to reach 900wh/kg.

● Safety

All solid state battery has the best safety because there is no liquid flammable electrolyte, no combustion, no leakage, no corrosion, etc. Semi-solid batteries are in the middle and liquid batteries are the worst.

● High and low temperature performance

All solid state battery has the best high-temperature performance and the worst low-temperature performance. Liquid batteries have the best low-temperature performance and the worst high-temperature performance.

● Battery lifespan

All solid state battery will last longer due to the absence of corrosion, leakage, etc. Semi-solid batteries are in the middle. Liquid batteries have room for improvement in terms of extending battery life.

● Malleability

Liquid batteries are now mature, semi-solid batteries are starting to move from the laboratory stage to the industrial stage, while all-solid batteries are in the laboratory stage of research.

Summary

All-solid-state batteries support thin-film designs for cells down to a few nanometres, broadening the range of applications for lithium-ion batteries and making it possible for batteries to be self-contained and flexible.

Due to their safety and potential high energy density, all-solid-state batteries are considered to be an important development direction for the next generation of power batteries. However, there are still bottlenecks such as low ionic conductivity of all-solid-state electrolytes, poor compatibility and stability of the electrode/electrolyte interface.