The operating principle of lithium-ion batteries is based on the embedding and de-embedding process of lithium ions between positive and negative electrode materials. In the charging state, lithium ions are de-embedded from the positive electrode material and migrate to the negative electrode through the electrolyte solution, where the negative electrode material is in a lithium ion-rich state. Conversely, during the discharge process, lithium ions are de-embedded from the negative electrode material and migrate back to the positive electrode. The capacity of the battery is mainly determined by the number of reversibly embedded and de-embedded lithium ions, and the performance parameters of the battery will change under different charging and discharging conditions or during the cycle. So, where does the lithium go?Lithium ions inside the battery are mainly stored in the following places:(1) Active lithium that moves and deintercalates between the positive and negative electrodes;(2) Unusable lithium that is embedded in the negative electrode layer and cannot be removed;(3) SEI film formed on the surface of negative electrode particles;(4) Lithium precipitated on the surface of negative electrode coating;(5) Lithium solvated in the electrolyte;(6) Lithium fluoride formed by decomposition of electrolyte;(7) CEI film formed on the surface of positive electrode particles;(8) Unusable lithium that cannot be removed from the inside of positive electrode materials.Figure 1 Schematic diagram of lithium distribution inside a lithium-ion batteryDuring the cycle of lithium-ion batteries, or under different charge and discharge rates and temperature conditions, the distribution of lithium inside the battery changes. Researchers at the University of Münster in Germany studied this.During the study, a T-shaped battery structure was first constructed. After the battery has been cycled or aged, it is disassembled and the following steps are performed:Figure 2 T-shaped battery structure diagram.The positive and negative electrodes are first cleaned with DMC, and then dissolved in water through microwave reaction. After the cleaning solution and dissolving solution are diluted with distilled water, the lithium content is determined using ICP technology..The diaphragm is soaked in hydrochloric acid, and the soaking solution is diluted and then tested for ICP lithium content..The nylon membrane used in battery assembly is washed and diluted with distilled water, and then tested for ICP lithium content..The other main components of the battery are also tested for ICP lithium content after being washed with distilled water.In addition, as a control, the researchers tested the lithium content of the battery that was cycled once at a 0.1C rate, assuming that a solid electrolyte interface (SEI) and a positive electrode electrolyte interface (CEI) film were formed on the electrode surface. The original negative electrode sheet does not contain lithium, so the lithium content of the negative electrode sheet of the control battery is regarded as the lithium content that forms the SEI film. The lithium content of the positive electrode sheet of the control battery minus the lithium content of the original electrode sheet is regarded as the additional lithium content that forms the CEI film. The accuracy of all test results is ±7%.

Specification:Operation temperature:Charge:0~55℃Discharge:-20~55℃Cycle life: 25±2℃,0.5C/0.5C,80%DOD，＞3000 times, Capacity retention≥80%Module to pack design makes battery system design tidy and neat.Comparing with producing battery with cells，modules offers benefits as following：1.  91.7% Work steps reduced.2.  91.7% Misoperation risk points reduced.3.  91.7% working time on battery internal assembly saved.4.  65-70% time shorter for one battery system assembly.5.  BOSA modules are designed universal to all BMS on the market, not limited to BMS types.BOSA ENERGY modules are widely applied on electric bus/truck/utility vehicles, light vehicle, Golf car ,forklifts and energy storage systems，including industrial and commercial ESS applications.With 5Gwh delivery in 2023 to over 30 countries,BOSA modules are well welcomed by more and more partners.Hope we will have chance to cooperate with you！For more information please feel free to contact us :Email ：info@bosaenergy.cnWebsite: www.bosaenergy.cn

Specification:Operation temperature:Charge:0~55℃Discharge:-20~55℃Cycle life:25±2℃,0.5C/0.5C,80%DOD，＞3000 times,Capacity retention≥80%Module to pack design makes battery system design tidy and neat.Comparing with producing battery with cells，modules offers benefits as following：1.91.7%Work steps reduced.2.91.7%Misoperation risk points reduced.3.91.7%working time on battery internal assembly saved.4.65-70%time shorter for one battery system assembly.5.BOSA modules are designed universal to all BMS on the market,not limited to BMS types.BOSA ENERGY modules are widely applied on electric bus/truck/utility vehicles,light vehicle,Golf car,forklifts and energy storage systems，including industrial and commercial ESS applications.With 5Gwh delivery in 2023 to over 30 countries,BOSA modules are well welcomed by more and more partners.Hope we will have chance to cooperate with you！For more information please feel free to contact us:Email：info bosaenergy.cnWebsite:www.bosaenergy.cn

BOSA participated in Eco-Mobil Gala on Schlossplatz in Schwetzingen Germany, On 31st August/1. September 2024, BOSA show its battery and battery powered vehicles on the fair. The platform attracted many visitors to watch.BOSA's battery has driven more than 1,000 classic vehicles, providing fashion power for these classic cars, making young people fall in love with them again, and driving these vehicles to accompany them to the places their grandpa used to like to go on weekends, reminiscing about their youth.BOSA ENERGY batteries are widely applied on electric bus/truck/utility vehicles, light vehicle, Golf car ,forklifts and energy storage systems，including industrial and commercial ESS applications.With 5Gwh delivery in 2023 to over 30 countries,BOSA batteries are well welcomed by more and more partners.Hope we will have chance to cooperate with you！For more information please feel free to contact us :Email ：info@bosaenergy.cnWebsite: www.bosaenergy.cn

Specification:         Operation temperature:Charge:0~55℃Discharge:-20~55℃Cycle life: 25±2℃,0.5C/0.5C,80%DOD，＞3000 times, Capacity retention≥80%Module to pack design makes battery system design tidy and neat.Comparing with producing battery with cells，modules offers benefits as following：1.  91.7% Work steps reduced.2.  91.7% Misoperation risk points reduced.3.  91.7% working time on battery internal assembly saved.4.  65-70% time shorter for one battery system assembly.5.  BOSA modules are designed universal to all BMS on the market, not limited to BMS types.BOSA ENERGY modules are widely applied on electric bus/truck/utility vehicles, light vehicle, Golf car ,forklifts and energy storage systems，including industrial and commercial ESS applications.With 5Gwh delivery in 2023 to over 30 countries,BOSA modules are well welcomed by more and more partners.Hope we will have chance to cooperate with you！For more information please feel free to contact us :Email ：info@bosaenergy.cnWebsite: www.bosaenergy.cn

1. Efficiency of lithium-ion batteriesThe efficiency of lithium-ion batteries mainly refers to the energy efficiency of the battery, that is, the ratio of the energy consumed by the battery to the energy stored. Under normal circumstances, the energy efficiency of lithium-ion batteries can reach more than 90%, which is much higher than other types of batteries.2. Key factors affecting the efficiency of lithium-ion batteries① Charging efficiency: During the charging process, electrical energy needs to be effectively converted into chemical energy and stored in the battery. Any factors that hinder this process, such as inappropriate electrolyte formulation, poor electrode structure or unsuitable operating temperature, may lead to reduced charging efficiency.② Discharge efficiency: Discharge efficiency refers to the ratio of the actual amount of electricity discharged to the terminal voltage under certain discharge conditions to the rated capacity of the battery. High discharge rate, low temperature or high internal resistance may limit the battery's ability to discharge, thereby reducing the discharge efficiency.③ Side reactions: During the battery charging and discharging process, the occurrence of side reactions will consume part of the electrical energy and reduce the battery's energy conversion efficiency. For example, side reactions such as electrolyte decomposition and active material dissolution will lead to a decrease in battery performance.3. Solutions to improve the efficiency of lithium-ion batteriesIn addition to optimizing the composition and properties of the electrolyte and optimizing the electrode materials during the production of the battery cell, it is also possible to:① Intelligent battery management: The intelligent battery management system can monitor, diagnose and optimize the battery in real time, thereby achieving efficient use of the battery.② Environmental factor control: Controlling the operating temperature within an appropriate range is an important measure to improve the efficiency of lithium-ion batteries. By adopting advanced thermal management systems or optimizing battery structures to improve heat dissipation conditions, the battery can be kept running at the optimal operating temperature, thereby improving its efficiency and stability.③ Integration and modular design: Integration is the combination of multiple single cells into a module or system to improve overall efficiency and stability. Modularization is the combination of multiple modules into a complete battery system. By optimizing integration and modular design, the internal resistance can be reduced, the energy density and safety can be increased, thereby improving the overall performance of lithium-ion batteries.