12v lithium battery protection circuit design requirements and functions.
12V lithium batteries are widely used in various fields such as digital
products, power tools, electric bicycles, electric vehicles, double power
supplies and energy storage. The design of lithium battery protection circuit is
very important. We require the 12v lithium battery power protection chip to
achieve the following most basic functions: overcharge protection,
over-discharge protection, over-current protection and short-circuit protection.
Improve the service life of lithium batteries and ensure the safe use of
batteries.
What is a 12v lithium battery?
12v lithium battery is made of 3 or 4 lithium batteries connected in
series. The capacity of the combined battery pack is determined based on the
capacity of a single cell or the capacity of batteries connected in parallel. It
is a new type of battery that is safe and environmentally friendly.
12v lithium battery parameters
Combination method: ICR18500-3S2P
Nominal voltage: 11.1V
Discharge voltage: 11.1V-12.6V
Conventional discharge current is: 0-2A, large capacity is 3-4A
Nominal capacity: in MahA, available in various sizes
Standard continuous discharge current: 0.2C
Maximum continuous discharge current: 1C
Working temperature: Charging: 0~45℃
Discharge: -20~60℃
12v lithium battery protection circuit design requirements
Due to the high energy density of 12v lithium batteries, in the overcharged
state, the energy will be excess after the battery temperature rises, so the
electrolyte decomposes to produce gas, which can easily increase the internal
pressure and cause the risk of spontaneous combustion or rupture; conversely, in
the overdischarged state, , the decomposition of the electrolyte leads to the
deterioration of battery characteristics and durability, reduces the number of
recharges, and shortens the service life of the battery. Therefore, the
protection of 12v lithium batteries is very important. 12v lithium battery
applications must have a battery protection chip to prevent overcharge,
overdischarge and overcurrent of the battery.
The 12v lithium battery protection circuit will increase the additional
loss of battery energy and reduce the battery's application time. This requires
the lithium battery protection circuit to achieve low power consumption with
high precision. In addition to completing basic functions such as overcharge
protection, over-discharge protection and over-current protection, a lithium
battery protection chip must also meet the following requirements:
(1) Ultra-low power consumption. When the lithium battery protection
circuit is working, the power consumption it consumes is the loss of the
battery. Therefore, we need to minimize the power consumption of the lithium
battery protection circuit.
(2) Highly accurate voltage detection. In order for the lithium battery
protection circuit to respond correctly to different working states of the
battery, the protection circuit must be able to accurately detect voltage
parameters such as overcharge protection voltage and over-discharge protection
voltage.
(3) Works correctly under a wide voltage range. Since the power supply
voltage of the lithium battery protection circuit is the battery voltage, and
the battery voltage can float within a wide range, the lithium battery
protection circuit is required to work correctly within this voltage range.
The 12v lithium battery protection circuit needs to have the following
functions
(1) If the charging voltage exceeds the maximum allowed value of the
battery, a battery discharge circuit can be provided.
(2) If the discharge voltage is lower than the minimum allowed value of the
battery, a battery charging circuit can be provided. then disconnect the battery
from the external circuit, and then disconnect the battery from the external
circuit, and
(3) If the charging and discharging current of the 12v lithium battery is
greater than the limit value, cut off the connection between the battery and the
external circuit.
(4) When the 12v lithium battery returns to normal state, the protection
circuit should be able to release the protection state accordingly so that the
battery can continue to work normally.
What are the main cathode materials of 12v lithium battery?
At present, my country's 12v lithium battery cathode materials mainly
include lithium cobalt oxide and ternary materials.
Lithium manganate and lithium iron phosphate. The application fields of
cathode materials are clearly differentiated. At present, lithium cobalt oxide
is still the main cathode material in the field of small lithium batteries and
is mainly used in traditional 3C fields. Ternary materials and lithium manganate
are mainly used in small lithium batteries and are used in Japan and South
Korea. The technology of power batteries is relatively mature and is mainly used
in fields such as power tools, electric bicycles and electric vehicles. Iron
phosphate 12V lithium batteries are used in the field of power batteries in
China and are the direction of future energy storage battery development. They
are mainly used in base stations and data Central energy storage, home energy
storage, wind and photovoltaic energy storage and other fields.
The ternary material combines the advantages of lithium cobalt oxide,
lithium nickel oxide and lithium manganate and has a price advantage. However,
its application is affected by the price of cobalt. When the cobalt price is at
a high level, the price of the ternary material is higher than that of lithium
cobalt oxide. Low, it has strong market competitiveness; but when the price of
cobalt is at a low level, the advantages of ternary materials compared to
lithium cobalt oxide are greatly reduced. At present, there is a general
development trend of lithium cobalt oxide materials being replaced by ternary
materials.
Read recommendations:
6F22
Lithium battery work principle.convenient energy storage power supply direct sales
What are the advantages of thick electrode design in the application of lithium-ion batteries?
li ion 18650 battery pack wholesaler
18650 li ion battery