Process
Main components of LiBs cell
The goal is to develop ever more powerful batteries that feature increased capacity, a longer lifetime, shorter charging times, lower weight and size.
Lithium ion batteries are basically comprised of a negative electrode (anode), a positive electrode (cathode) and a separator membrane. The individual electrodes are made up of conductor foils that are coated with a mixture of binders, active materials and additives (battery slurries). For more efficient energy storage and energy output, it requires of sophisticated analysis of the characteristics of component of batteries.
It is necessary to analyze the thermal properties of separator, electrolytes, cathode and anode to suit the design of each battery. For example, one can measure the heat capacity and thermal conductivity of electrodes with the same pore size, or analyze the thermal behavior of the electrodes under high pressure. This allows you to develop methods for batteries quality control.
It is a key material that determines the performance of a battery (capacity, average voltage). As it accounts for 40% of the production cost, it is a big part in the battery industry. The higher the nickel content in the cathode material, the more the battery capacity can be increased.
Determine the capacity: Need the high capacity, low price
The kinds of cathode materials
- LCO (Lithium Cobalt oxide, LiCoO2)
- NCA (Lithium Nickel Cobalt Aluminum oxide, LiNiCoAlO2)
- NCM (Lithium Nickel Magnesium Cobalt oxide, Li[NiCoMn]O2)
- LMO (Lithium Magnesium Oxide, LiMn2O4)
- LFP (Lithium iron phosphate, LiFePO4)
It is a material that stores ithium ions when charging the battery. Carbon materials, such as graphite, are often used as a material of the anode material.
Chemical reaction with the cathode: Need the large output
The kinds of cathode materials
- Graphite (Natural, Synthesis)
- Lithium Titanate (LTO)
- Alloying Materials (Silicon, Tin)
- Silicon Oxide (SiOx)
In order to prevent an internal short-circuit in the cells, a separator is placed between the electrodes. The separators, which are typically made of plastic (e.g. PE, PP), are perforated to allow the ions to pass through.
If Separator is shrunk or ruptured, electrical short may occur. Then Battery explode. Therefore, Separator is key component for LiBs Safety.
For increased thermal stability and the prevention of shrinkage, so-called Inorganic Composite Separators (ceramic-coated foils) are finding increased use.
Prevention of short circuit: Need high safety and reliability
The majority of active materials are oxides with limited electrical conductivity. That is why additives that reduce the required charging time of the battery are added to the battery slurries. Here it is primarily the carbon-based raw materials that are used, such as carbon black, graphite and carbon nano tubes (CNT), which should be characterized by the highest possible aspect ratio.
The materials must first be carefully dispersed or delaminated in preliminary stages.
