What are the advantages and disadvantages of lithium titanate batteries.

Disadvantages of lithium titanate battery

Advantage

Replacing fuel vehicles with electric vehicles is the best choice for solving urban environmental pollution. Among them, lithium-ion power batteries have attracted wide attention of researchers. In order to meet the requirements of electric vehicles for on-board ion power batteries, high safety and high rate performance have been developed. And the long-life anode material is a hot spot and a difficult point.

The commercial lithium-ion battery anode mainly uses carbon material, but the lithium battery with carbon as the negative electrode still has some drawbacks in application:

1. Lithium dendrites are easily precipitated during overcharging, causing short circuit of the battery and affecting the safety performance of the lithium battery;

2. Easy to form SEI film, resulting in lower initial charge and discharge efficiency, irreversible capacity;

3. That is, the carbon material has a low platform voltage (close to metallic lithium), and easily causes decomposition of the electrolyte, thereby posing a safety hazard.

4. The volume change is large during the process of lithium ion insertion and extraction, and the cycle stability is poor.

Compared to carbon materials, the spinel-type Li4Ti5O12 has obvious advantages:

1. It is a zero strain material with good cycle performance;

2. The discharge voltage is stable, and the electrolyte does not decompose, improving the safety performance of the lithium battery;

3. Compared with the carbon negative electrode material, lithium titanate has a high lithium ion diffusion coefficient (2*10-8 cm2/s), and can be charged and discharged at a high rate.

4. The potential of lithium titanate is higher than that of pure metal lithium, which is not easy to produce lithium crystal branches, which provides a basis for ensuring the safety of lithium batteries.

Disadvantage

1. The energy density of other types of lithium-ion power batteries will be lower.

2. The problem of flatulence has been hindering the application of lithium titanate batteries.

3. Relatively high prices for other types of lithium-ion power batteries.

4. There is still a difference in battery consistency. As the number of charge and discharge times increases, the difference in battery consistency will gradually increase.

The lithium titanate battery is a lithium ion secondary battery which is used as a negative electrode material for a lithium ion battery, lithium titanate, and can be composed of a positive electrode material such as lithium manganate, a ternary material or lithium iron phosphate to form a 2.4V or 1.9V. In addition, it can also be used as a positive electrode, and a 1.5V lithium secondary battery is composed of a lithium metal or a lithium alloy negative electrode due to the high safety, high stability, long life and green environmental protection of lithium titanate.

It is foreseeable that lithium titanate materials will become the anode material of a new generation of lithium-ion batteries after 2-3 years and are widely used in new energy vehicles, electric motorcycles and require high safety, high stability and long cycle application area. The lithium titanate battery has a working voltage of 2.4V, a maximum voltage of 3.0V, and a charging current greater than 2C (ie, a current of twice the battery capacity value).

Lithium titanate (LTO) material is used as a negative electrode material in batteries. Due to its own characteristics, the material and the electrolyte are likely to interact with each other and produce gas evolution during the charge and discharge cycle reaction. Therefore, ordinary lithium titanate the battery is prone to flatulence, resulting in a battery pack, and the electrical performance is also greatly reduced, greatly reducing the theoretical cycle life of the lithium titanate battery. The test data shows that the ordinary lithium titanate battery will explode after 1500-2000 cycles, which may cause normal use, which is an important reason for restricting the large-scale application of lithium titanate batteries.

Lithium titanate (LTO) battery performance improvement is a combination of improved performance of individual materials and organic integration of key materials. In response to the requirements of fast charging and long service life, in addition to the anode material, other key raw materials for lithium-ion batteries (including cathode materials, separators, and electrolytes), combined with special engineering process experience, have finally formed The non-flatulence lithium titanate LpTO battery product, and first realized the batch application on the electric bus.

The test data shows that under the conditions of 6C charging, 6C discharge and 100% DOD, the lithium titanate LpTO single cell has a cycle life of more than 25,000 times, and the remaining capacity exceeds 80%. At the same time, the flatulence generated by the battery is not obvious and does not affect. Its lifespan; and the practical application of Chongqing fast-charging pure electric bus also shows that after the battery is grouped, the performance of electric performance is also very good, which can guarantee the daily commercial operation of pure electric bus.

Advantage

Replacing fuel vehicles with electric vehicles is the best choice for solving urban environmental pollution. Among them, lithium-ion power batteries have attracted wide attention of researchers. In order to meet the requirements of electric vehicles for on-board ion power batteries, high safety and high rate performance have been developed. And the long-life anode material is a hot spot and a difficult point.

The commercial lithium-ion battery anode mainly uses carbon material, but the lithium battery with carbon as the negative electrode still has some drawbacks in application:

1. Lithium dendrites are easily precipitated during overcharging, causing short circuit of the battery and affecting the safety performance of the lithium battery;

2. Easy to form SEI film, resulting in lower initial charge and discharge efficiency, irreversible capacity;

3. That is, the carbon material has a low platform voltage (close to metallic lithium), and easily causes decomposition of the electrolyte, thereby posing a safety hazard.

4. The volume change is large during the process of lithium ion insertion and extraction, and the cycle stability is poor.

Compared to carbon materials, the spinel-type Li4Ti5O12 has obvious advantages:

1. It is a zero strain material with good cycle performance;

2. The discharge voltage is stable, and the electrolyte does not decompose, improving the safety performance of the lithium battery;

3. Compared with the carbon negative electrode material, lithium titanate has a high lithium ion diffusion coefficient (2*10-8 cm2/s) and can be charged and discharged at a high rate.

4. The potential of lithium titanate is higher than that of pure metal lithium, and it is not easy to produce lithium dendrites, which provides a basis for ensuring the safety of lithium batteries.

Disadvantage

1. The energy density of other types of lithium-ion power batteries will be lower.

2. The problem of flatulence has been hindering the application of lithium titanate batteries.

3. Relatively high prices for other types of lithium-ion power batteries.

4. There is still a difference in battery consistency. As the number of charge and discharge times increases, the difference in battery consistency will gradually increase.

Industry dynamic editing

The "Scib" lithium battery produced by a Japanese company, the negative electrode is a lithium titanate material, which has been applied in batches with the "EV--neo" electric motorcycle.

Since April 2011, Chongqing Public Transport Group has started to operate fast-charged pure electric buses in batches of 689 and 687 roads in Chongqing. So far, the first vehicles have been in operation for two years. The core of these vehicles is the micro-power lithium titanate LpTO battery and the "10-minute fast charging technology" passed the rigorous test of the actual commercial operation of the bus, and the overall performance is excellent.

Domestic Zhuhai Yinlong New Energy Co., Ltd. has mass-produced lithium titanate battery application and energy storage at the end of 2009, and acquired 51% of the global lithium titanate technology leading US Nasdaq listed company in November 2010 with 51 billion yuan holding 51% ALTAIR. Chinese companies that are beginning to get involved in the battery business have increased their technological capabilities by acquiring US companies. This approach is the most direct expression of the fierce momentum of today's Chinese companies staged the first case of China's battery industry cross-border acquisition.

There are many research units in China that are promoting the research of Li4Ti5012 anode materials, such as Tianjin University, Tianjin Power Research Institute, Beijing University of Science and Technology, Xiamen University, Wuhan University, Chengdu Institute of Chinese Academy of Sciences, Shenzhen Research Institute of Tsinghua University, etc. are doing research in this area.

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