solutions
Requirements for positive (cathode) material CORRECT ANSWERS 1, in an
intercalation compound, the metal ion should have a high redox potential to
achieve high output voltage
2, To ensure good cycling performance, intercalation and deintercalation of Li+
should be reversible during the whole charge-discharge process, and the volume
change should be little or none in the main host structure
3, The change of redox potential with x should be as small as possible, so that the
output voltage of the battery doesn't change much and can maintain relatively
stable
4, The intercalation compound should have good electronic conductivity and Li+
conductivity (diffusion coefficient) to reduce polarization
5, The intercalation compound should have good chemical stability and should not
react with electrolyte over the entire voltage range (minimize of side reactions)
6, From the viewpoint of practical application, the compound should be
inexpensive, nontoxic, and environmentally friendly.
Classification of cathode materials CORRECT ANSWERS Olivine
Layered transition-metal oxides
Spinel frameworks
TEM CORRECT ANSWERS Metal as black
Nano scale
, SEM CORRECT ANSWERS Metal as white
Micro scale
Which layers structure has the highest capacity CORRECT ANSWERS Layered
Which layers structure has the highest avg potential CORRECT ANSWERS Spinel
What is the structure of LCO(Lithium Cobaltate) CORRECT ANSWERS Layered
Advantage of LCO CORRECT ANSWERS good conductivity
Capacity of LCO CORRECT ANSWERS 120-140mAh/g
Average working voltage of LCO CORRECT ANSWERS 3.7V
Disadvantage of LCO CORRECT ANSWERS Toxic
Hard to be recycled
Expensive
Capacity is not high enough
Unstable at high temp, resulting in severe self-discharge