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Today we're going to talk about battery winding process. Choosing the right equipment is sometimes the key to doing a good job, especially when it comes to research and manufacturing lithium ion batteries. We, TOB New Energy, as a global professional lithium battery equipment supplier in particular understand this truth. This cylindrical cell winding machine is mainly used for 18650, 21700, 26650, 26700, 32650 cells. TOB-JR135-P pouch cell semi-automatic winder machine is used for winding battery anode and cathode with separator together in the research of Li-ion Pouch cell batteries. Here are a few key points need to pay attention to when we during the 18650 lithium battery winding process. 1.Humidity control ≤1%RH Purpose: To prevent water absorption in the battery winding process of cathode and anode electrode, resulting in poor zero voltage, self-discharge and bad cycling performance; Method:calculate the dew point and the temperature got the value. 2.  Powder control≤100，000pc/ft3，(detect diameter is 0.5um) Objective: To prevent dust from being involved in the electrode during winding, resulting in short circuit, overheat, fire and self-discharge of the cell. Methods: Dust tester was used. 3.  Abnormal cutting burr Process requirement:electrode ≤8um tabs burr≤12um Adverse effects: Burr of electrode or tabs exceeding process requirements may cause burr to Pierce diaphragm, short circuit of anode and cathode, overheat of electric cell, explosion may occur in serious cases, and serious safety hazard exists. 4. The coverage of cathode and anode Process requirements: the alignment of cathode and anode is 0.75mm Alignment of anode with separator 1.5mm Adverse effects: The alignment of cathode and anode maybe cause anode not wrap the cathode when the cell charge, the Li-ion come out of the cathode will not find the corresponding graphite to be embedded, which causes the free lithium ions in the battery cell to accumulate on the anode and produce dendrites. The dendrites puncture the separator and cause internal short circuit, thus causing potential safety hazards. The alignment between anode and the separator over the process requirement maybe will cause the anode be squeezed and deformed. Part of the powder on the electrode fall out, during the charge the cell will expand, and the powder will puncture the separator cause cathode and anode inner short circuit and cause the safety hazard.

As the core component of new energy vehicle, the quality of lithium ion battery directly determines the performance of the vehicle.Lithium ion battery manufacturing equipment generally consists of three types: front-end equipment, mid-end equipment, and back-end equipment. The precision and automation level of the equipment will directly affect the production efficiency and consistency of the products. As an alternative to traditional welding technology, laser processing technology has been widely used in lithium battery manufacturing equipment. Application of Laser welding in the production of lithium battery Welding is a very important manufacturing process from the manufacturing of lithium ion battery cell to the battery PACK. The conductivity, strength, air tightness, metal fatigue and corrosion resistance of lithium ion battery are typical evaluation standards for battery welding quality.The choice of welding method and welding process will directly affect the cost, quality, safety and consistency of the battery. Laser welding has high energy density, small welding deformation and small heat-affected zone, which can effectively improve the precision of the workpiece. The welding seam is smooth and free of impurities, uniform and compact, and no additional polishing is required.Laser welding can be accurately controlled, with small focal point, high precision positioning, easy to realize automation with mechanical arm, improve welding efficiency, reduce working hours, reduce cost;In addition, laser welding of thin plate or thin diameter wire rod will not be subject to the trouble of remelting as easily as arc welding, and it can be welded with a wide variety of materials, which can realize the welding between different materials. The characteristics of laser processing lithium ion battery (1) welding refractory materials such as titanium, quartz, etc., and can be used to weld the opposite material, the effect is good. (2) After laser focusing, the power density is high. In the welding of high-power devices, the depth-width ratio can reach 5:1, and the height can reach 10:1. (3) Can be at room temperature or special conditions for welding, welding equipment is simple.For example, a laser beam is not deflected by an electromagnetic field. It can be welded in a vacuum, air, or some gas environment, and can be welded through glass or through a transparent material of the beam. TOB NEW ENERGY LIMITED is specialized in lithium battery industry, our company can provide you a turnkey project, if you are interested in it, feel free to contact us! Thank you for reading!

Coating process is a process based on the study of the physical properties of fluids, in which one or more layers of liquid are coated on a substrate, usually a flexible film or lining paper, and then the coated liquid coating is dried or cured in an oven to form a film layer with special functions. At present, the most important coating methods for lithium ion battery are comma-roller transfer coating and slit extrusion coating. The properties of coating solution itself have a great influence on coating results.The shear rate-viscosity data of the coating solution is an important consideration before you apply the coating.When the coating solution has a very strong viscoelasticity, usually about the coating process, will bring greater difficulty. Viscoelasticity is the reaction of viscosity and elasticity after fluid deformation. Some fluids have only viscosity change under shear force, while more complex fluids have strong elastic energy after shear deformation.How do you determine the viscoelastic energy of a fluid?It can be judged by the curve of shear force and viscosity. After the pressure release, this change in the fluid will greatly affect the effect of coating. What effect does that have? In the slit coating, if the solution with a greater shear force from the coating head lip extrusion, or with a faster speed coating, because the solution in the coating after completion, in the case of pressure release, there will be shrinkage, resulting in the formation of similar vertical stripes.Even in severe cases, retraction of the solution can result in electrode creases and crimping. So how do you prevent these defects? In the slit coating process, we have to be very careful to control the flow of fluid in the coating head, so that the solution is very uniform flow out of the lip, and the solution of the shear force as much as possible to control to the minimum. Generally speaking, the general coating solution has the ability of self-leveling, and viscoelastic body is not easy to flow, so the formation of the film will be a little lower. When you want to coat a viscoelastic body, you must first fully understand the reaction of the polymer with a higher molecular weight under stress, so as to better offset the resulting defects in the coating process through control of the process. In general, making this kind of fluid coating under low shear force is the best way to reduce the probability of defects!

Lithium ion battery forming is the first charge process of the lithium ion battery.The purpose of this work is to make lithium ion battery have the electrochemistry active.The forming process is forming a solid electrolyte interface film(SEI film),the SEI film have the character of the solid electrolyte interface,is a electronic insulator but this film is a excellent conductor for Li+,the Li+can pass the SEI film freely.The important ingredient of the SEI film is Li2CO3、LiF、LiOH、ROCO2Li、ROLi etc.The quality of the SEI film have a big relativity with the forming process,if the forming process is not good,it could not forming a high quality SEI film,and then the will have bad influence of the cycle life and the electrochmistry performance. The forming process can activate the cathode and the anode material have the electrochmical reaction and the forming film ingredient of the electrolyte forming the SEI film at he surface of the anode,effectively prevent the reaction of the solvent and the anode active materials,admit the de-intercalation of the Li+.The state of the Li+directly influence of the battery anode interface,capacity performance,self discharge,cycle performance and safety performance. TOB New Energy can provide full set of battery formation charge and discharge machine. They are suitable for coin cell,pouch cell and cylindrical battery formation and grading in battery production line manufacturing.

A batch of battery formation and grading machine and other testers for the 18650 production line have been completed, they will soon be arranged to be shipped to the customer's factory by container. About the battery formation and grading machine detection system: 1. Scope of application: chemical composition and detection of lithium polymer, lithium ion, nickel hydrogen, and nickel cadmium batteries. 2. According to the design of the equipment manufacturer, there are entire control, single point start and single point stop for each channel. 3. It can work independently without a computer. The middle computer has its own keyboard and large-screen LCD English display, which is simple, convenient and intuitive to operate. 4. Using network connection and SQL database, centralized control of multiple connected cabinets, and centralized management, analysis and statistics of all data. 5. Modular design, easy to maintain. The hardware technology is advanced, stable and durable. TOB NEW ENERGY LIMITED is specialized in lithium battery industry, our company can provide you a turnkey project, if you are interested in it, feel free to contact us! Thank you for reading! Contact person:Gavin Zhu (Engineer & Sales) Email:tob.gavin@tobmachine.com Skype: tob.gavin@tobmachine.com Wechat: TOB-007

Battery cathode is one of the core component part of the battery,its advantages and disadvantages directly affect the battery performance. Generally speaking, cathode active substances are required as follows: ·Allow a large amount of Li+ embedding and ejecting (large capacity); ·High REDOX potential (high voltage); ·Good reversibility of embedding and ejection, small structural change (long cycle life); ·High lithium ion diffusion coefficient and electronic conductivity (low temperature, good multiplier characteristics); ·High chemical/thermal stability, good compatibility with electrolyte (good safety); ·Abundant resources, environment-friendly, cheap price (low cost, environmental protection). Generally speaking, the key performance indexes of cathode electrode materials include chemical composition, crystal structure, particle size distribution, vibrational density, specific surface area, pH value, specific capacity of first discharge, efficiency of first charge and discharge, cycle life, etc. Most of the cathode materials of the lithium battery is lithium oxide,generally the higher lithium content,the higher of the capacity.Like the Li content of the LMO is about 4.2%,and this value of LCO and LNO is about 7.1%.Lithium-manganese rich can be as high as about 10%.When material composition is fixed, the principal element content should be given in the form of actual test averages add tolerances to achieve the corresponding electrochemical activity and maintain stability between batches. The size of cathode materials will directly affect the preparation of battery slurry and electrode sheet. Generally, the size of large-size materials has low viscosity, good fluidity, less solvent and high solid content. The particle size of cathode electrode materials is usually measured by laser particle size analyzer.The equivalent diameter D50 of the largest particle when the cumulative distribution in the particle size distribution curve is 50% regard as average particle size.The particle size and distribution of positive electrode materials are closely related to the precursor, sintering and crushing process, and should be normally distributed under normal circumstances.Generally, lithium cobalt oxide and lithium carbonate are used as raw materials for the preparation of lithium cobalt oxide. Its sintering characteristics are very good, and it can be grown by controlling key factors such as Li/Co, sintering temperature and heating rate, so the requirements for raw materials are relatively low.Large abnormal-shaped particles are easy to appear in the powder materials grown and broken through sintering adhesion, and scratches and broken belts are easy to appear in the pulping coating and forming process. Therefore, the lithium cobalt oxide standard restricts the equivalent diameter Dmax of the largest particles in the particle size distribution curve.  

After there have a lot of customer feedback,and we introduce a new design semi-auto stacking machine. 1.    We changed part of the structure of the machine,compare with former stacking machine,we increase the height of the machine now,after these little change we can directly operate the machine in the ground rather than need put the machine in the table.and make the operate more convenience. 2.    We simplify the operate of the HMI screen of the battery stacking machine,it just have 3 interface of the machine now to ensure that our customer learn and use it easier. 3.    For the metal plate,we made a little change of it.For the former battery stacking machine,it is more sharp and angular.And now we made it more mellow and full,which made the battery stacking machine more beautiful and improved the safety of the machine,reduce the possibility of the human got injured. And the new battery stacking machine still remain the merit of former machine. 1.    All of the stacking process is automatic and we just need manually feeding the electrode and then take out the finished product. 2.    the move of the stacking sucking disc is controlled by the servo motor can convenient record the position of the sucker and have a high precision of the position which can ensure the stacking result. 3.    And for the electrode size of the battery stacking machine it is can be customized according requirement.

High temperature tube furnace, openable high temperature tube furnace liner made of light high temperature fiber material, composed of two semi-circular furnace bodies, easy to open, can be divided into vertical and horizontal, and can be installed on a designated furnace rack , Or install the furnace body on other work surfaces as needed, the furnace body and the controller can be integrated or separated. It has up to 32 heating program functions. Just turn on the power supply to set the program, the machine will work automatically and shut down automatically when the work is completed; the instrument is easy to operate, fast heating speed, adjustable heating speed, and lightweight. Main uses: widely used in ceramics, metallurgy, electronics, glass, chemicals, machinery, refractory materials, new material development, special materials, building materials, universities, scientific research institutes, industrial and mining enterprises for powder roasting, ceramic sintering, high temperature experiments, material processing ,quality inspection. If you are interested in it, please feel free to contact me. Thank you for reading! Contact person:Gavin Zhu (Engineer & Sales) Email:tob.gavin@tobmachine.com Skype: tob.gavin@tobmachine.com Wechat: TOB-007