LiFePo4 Battery Cell 26650 32700 With Screws For 12V 40AH Small
Battery Pack
| species |
Lithium Iron Phosphate |
Voltage | 32700-12V |
capacity | 40AH |
Batteries | IFR32700 3.2V 6Ah |
size | 195*131*185mm |
weight | 6.5KG |
Maximum charging current | 50A |
Maximum discharge current | 50A |
Display screen | Yes |
Communication support | Bluetooth/S485/CAN |
Research status of high-pressure lithium cobalt oxide materials
At present, the most widely studied and widely used high-voltage
cathode material is lithium cobalt oxide, which has a
two-dimensional layer. The structure, α-NaFeO2 type, is more
suitable for the insertion and expulsion of lithium ions. The
theoretical energy density of lithium cobalt oxide is 274mAh/g,
which has the advantages of simple production process and stable
electrochemical properties, so it has a high market share. In
practical applications, only some lithium ions can be reversibly
embedded and expelled in lithium cobalt oxide materials, and its
actual energy density is about 167mAh/g (working voltage is 4.35V).
Increasing the operating voltage can significantly increase its
energy density, for example, increasing the operating voltage from
4.2V to 4.35V can increase the energy density by about 16%.
However, under high voltage, lithium ions are embedded and detached
from the material many times, which will cause the structure of
lithium cobalt oxide to change from trigonal crystal system to
monoclinic crystal system, and the lithium cobalt oxide material no
longer has the ability to embed and excrete lithium ions, and the
particles of the cathode material will loosen and fall off from the
current collector, resulting in the internal resistance of the
battery becoming larger and the electrochemical performance
worsening.
At present, the modification of lithium cobalt oxide cathode
materials is important to improve the crystal structure stability
and interface stability of the materials from two aspects: doping
and coating.
At present, lithium cobalt oxide high-voltage materials have been
used in batches in high-energy-density batteries, such as high-end
mobile phone battery manufacturers have higher and higher
requirements for battery performance, which is important in the
higher requirements for energy density, such as the energy density
of 4.35V mobile phone batteries with carbon as the negative
electrode is required to be about 660Wh/L, and the 4.4V mobile
phone battery has reached about 740Wh/L, which requires the cathode
material to have a higher compaction density and higher air volume.
As well as better stability of the material structure under high
compaction and high voltage. However, lithium cobalt oxide
electrode materials have shortcomings such as lack of cobalt
resources and high price, and cobalt ions have certain toxicity,
which limit their wide application in power lithium batteries.
