Battery Power Module
Battery Cell: The smallest unit that makes up the battery power module. It is generally composed of a positive electrode, a negative electrode, an electrolyte and a housing. Can realize direct conversion between electrical energy and chemical energy;
Battery module: a combination of a group of parallel battery cells. The rated voltage of the combination is equal to the rated voltage of the battery cell. the connected grouping in the physical structure and circuit can be replaced as a unit;
Module: A combination consisting of several battery modules or single cells connected in series.
The C30DB project uses a lithium-ion battery system
The lithium-ion battery is a rechargeable battery that mainly relies on lithium ions between the positive poles. and the negative electrodes. During the floatge, the lithium ions are deintercalated from the positive electrode and integrated into the negative electrode via the electrolyte. The negative electrode is in a lithium-rich state; the opposite is true during discharge. Lithium ion batteries can be divided into lithium cobalt oxide batteries, lithium manganate batteries, lithium iron phosphate batteries and three-element batteries according to different cathode materials.
How to balance 6s battery with large voltage difference
First of all, polymer batteries are also a type of lithium battery. As long as you remove the label from the outer packaging of the battery, you can easily distinguish it when you see the battery core. The silver plastic packaging is a polymer battery, and the metal shell is a common mobile phone lithium battery.
Supplement:
Lithium polymer batteries are better.Compared with lead-acid batteries of the same capacity, the weight and volume are 1/3 to 1/4 of lead-acid batteries. Mainly used in mobile phones, laptops, PDA personal data assistants, video cameras, digital cameras, electric vehicles, etc.
1 Structural characteristics of lithium-ion batteries
The positive and negative aspects of lithium-ion batteries Extremely active materials are intercalated compounds. When charging, Li+ is detached from the positive electrode and inserted into the negative electrode when discharging, the opposite is true. The battery is actually the process by which Li+ is integrated and detached back and forth between the two electrodes, so this type of battery is also called “Rocking Cells” (abbreviated as RCB). The schematic diagram of the reaction and the basic reaction formula are as follows:
2. Lit battery technologylithium-ion polymer batteries
2.1 Performance characteristics of lithium-ion polymer batteries
Polymerization Physical lithium-ion batteries refer to lithium-ion batteries that use a solid polymer electrolyte (SPE ) as an electrolyte. The battery is composed of a positive electrode current collector, a positive electrode membrane, a polymer electrolyte membrane, a negative electrode membrane and a current collector. negative electrode. The battery is composite pressed and formed, and is wrapped in an aluminum-plastic composite. The film and its edges are hot melted and sealed to obtain a lithium-ion polymer battery. Since the electrolytic membrane is solid, there is no leakage problem and the battery design has greater freedom. It can be connected in series and parallel or adopt a bipolar structure according to needs.
Lithium-ion polymer batteries prhave the following characteristics: ① Formatting flexibility; ② Higher mass specific energy (3 times that of MH-Ni batteries) ③ Wide electrochemical stability window, up to 5V;; ④ Perfect security and reliability; ⑤ Longer life and less capacity loss; ⑥ High volume use;
Work performance indicators are as follows: working voltage: 3.8V; specific energy: 130 Wh/kg, 246 Wh/L; lifespan: > 300; : 253-328K; Charging speed: 1 hour at 80% capacity; 3h at 100% capacity;
2.2 Cathode material
The characteristics and price of lithium-ion batteries are closely related to their cathode material. Generally speaking, the cathode material should meet: ⑴ the required charge and discharge. potential In the range, it has electrochemical compatibility with the electrolyte solution; (2) soft electrode process kinetics; (3) onee high reversibility (4) good stability in air in the complete lithium state. With the development of lithium-ion batteries, research is constantly being carried out on high-performance and inexpensive cathode materials. At present, research mainly focuses on lithium and transition metal oxides such as lithium cobalt oxide, lithium nickel oxide and lithium manganese oxide [1] ( see table 1). Lithium cobalt oxide (LiCoO2) belongs to the α-NaFeO2 type structure and has a two-dimensional layered structure, suitable for the deintercalation of lithium ions. Due to its relatively simple preparation process, stable performance, high specific capacity and good cycle performance, most lithium-ion batteries currently on the market use LiCoO2 as the cathode material. Synthesis methods mainly include synthesis inhigh temperature solid phase and low temperature solid phase synthesis, as well as mild chemical methods such as oxalic acid precipitation, sol-gel method, hot and cold method and organic mixing method.
Lithium nickel oxide (LiNiO2) is a rock salt-like structural compound with good high temperature stability. Due to its low self-discharge rate, low electrolyte requirements, no environmental pollution, relatively abundant resources and affordable price, it is a promising cathode material for replace lithium cobalt oxide. At present, LiNiO2 is mainly synthesized by solid phase reaction of Ni(NO3)2, Ni(OH)2, NiCO3, NiOOH and LiOH, LiNO3 and LiCO3. The synthesis of LiNiO2 is more difficult than that of LiCoO2. The main reason is that stoichiometric LiNiO2 easily decomposes into Li1-xNi1+xO2 dan high temperature conditions. Excess nickel ions are found in the lithium layer between the NiO2 planes, preventing lithium diffusion. This will affect the electrochemical activity of the material. At the same time, because Ni3+ is more difficult to obtain than Co3+, the synthesis must be carried out in an oxygen atmosphere [2].
Lithium manganese oxide is a modification of traditional cathode materials. Currently, spinel-type LixMn2O4 is widely used. It has a three-dimensional tunnel structure and is more suitable for the deintercalation of lithium ions. Lithium manganese oxide contains abundant raw materials, low cost, no pollution, better overcharge resistance and thermal safety, and has relatively low requirements for battery safety protection devices. It is considered the most popular lithium-ion battery cathode materials promising. Manganese dissolution, the Jahn-Teller effect, and electrolyte decomposition are considered to make lithium manganese oxide a positive electrode. The materials are the primary cause of capacity loss in lithium-ion batteries. ion.
2.3 Solid polymer electrolyte
Solid materials that conduct current through ions are generally called solid electrolytes, which include crystalline electrolytes, glass electrolytes, and polymer electrolytes ( EPS). advantages of light weight, easy film forming and good viscoelasticity, and can be used in batteries, sensors, electrochromic displays, capacitors, etc. The use of SPE in lithium-ion batteries can eliminate the problem of easy leakage of liquid electrolytes, replace the insulation membrane in the battery, inhibit the generation of dendrites on the electrode surface, reduce the reactivity inbe the electrolyte and the electrode, increase the specific energy. of the battery and makes the battery more durable in terms of pressure, shock resistance, low production cost and easy repair instrument of battery pressure difference balance.
1. Firstly, you can use the battery pressure difference balance repair instrument to equalize the battery pressure difference. After repair, the lithium battery can reach the factory pressure difference state.
2. Second, use direct current equal to the battery's design voltage to charge the battery so that the voltage can return to the designed level.
3. Finally, for lithium batteries that cannot be balanced, you can choose a new battery and pair the battery.