Since coming out 1990, lithium battery because of its energy density tall, environmental protection, life grows tall, voltage and can charge quickly wait for an advantage, get the favour of the industry such as tool of 3C number, power, its are highlighted particularly to the contribution of industry of automobile of new energy resources. Regard the lithium battery that provides source of power of car of new energy resources as the industry, market potential is tremendous, be national strategy development is important one annulus, predicting future 5-10 year, industrial dimensions hopeful breaks through 160 billion yuan. Dynamical cell regards the core of car of new energy resources as the component, its character decided directly truckload function. Lithium battery production device is front commonly equipment, medium upright equipment, back end equipment 3 kinds, its equipment precision and automation level will affect the manufacturing efficiency of the product and consistency directly. And technology of laser beam machining replaces a tradition to solder as a kind the technology applies Yu Li extensively already in electric production equipment. The article passes laser to use a case mediumly in dynamical cell industry, elaborated the craft characteristic that laser beam welding receives, analysed aluminium alloy laser beam welding to receive difficulty and solder pattern is right solder the influence of quality, listed quadrate power cell and characteristic of batteries PACK craft and equipment development trend. Laser beam welding receives core of report of batteries of craft Cong Li make batteries PACK become group, soldering is a very important production working procedure, fatigue of the conductivity of lithium battery, intensity, air-tightness, metal and corrosion resistance, the batteries that is a model solders quality evaluates a standard. Solder method and solder of craft choose, the consistency of the cost that affects cell directly, quality, safety and batteries. In numerous solder in means, laser solders to show itself with following advantages: Above all, laser beam welding receives energy density tall, solder be out of shape small, heat affects an area small, rise effectively make a precision, welding line is not had glossily even and foreign matter, compact, need not additional burnish works; Next, laser beam welding is received can control accurately, focusing spot is small, high accuracy fixed position, cooperate manipulator arm to implement automation easily, rise solder efficiency, reduce man-hour, reduce cost; Additional, when laser beam welding receives laminose material or careful path wire, won't solder to be answered the worry of frit easily in that way like electric arc. The structure of batteries contains a variety of material normally, wait like steel, aluminous, copper, nickel, these metals may be made electrode, lead, or it is crust; Accordingly, no matter be the occasional of a kind of material,be a variety of material between solder, all to soldering craft raised taller requirement. The material qualitative sort that the craft dominant position that laser beam welding accepts depends on can soldering is extensive, can realize different material between solder. Because the production of core of report of cell of craft difficulty power is abided by " light " principle, can use normally relatively " light " aluminous material is qualitative, and do even more " thin " , the ply of general case, lid, bottom asks basically to achieve 1. 0mm is the following, at present the basic material ply of manufacturer of a few mainstreams all is in 0.
8mm left and right sides. According to statistic, the batteries housing of aluminium alloy material occupies the 90% above of whole power cell. The difficulty that aluminous material solders is opposite at aluminium alloy the tall thermal conductivity of the tall initiative reflectivity that stimulates beam of light and its itself, make aluminium alloy low to the absorptivity of laser before fusing, because aluminous ionization can be low, solder the light in the process sends plasma not to diffuse easily, make solder stability is poor. Additional, solder of the alloying element in the process burn caustic, make aluminium alloy solders the mechanical function of contact drops. Because solder stomatic sensitivity is tall in the process, blemish of a few problems can appear inevitably when soldering, among them the mainest is air hole and hot crack. The laser beam welding of aluminium alloy receives the stoma of the generation in the process to basically have two kinds: Hydric aperture and spoon aperture are undone the stoma of generation. The cooling rate that solders as a result of laser is too rapid, hydric aperture problem is more serious, and solder in laser in much still the hole of a kind of as a result of the cave in of alveolus generation. Hot crack problem. Aluminium alloy belongs to a model in all brilliant alloy, when soldering appear easily hot crack, include crackle of welding line crystallization and HAZ liquefacient crackle, because composition of welding line region slants,analyse can happen in all brilliant slants analyse and occurrence crystal boundary is fused, liquefacient crackle is formed in crystal boundary place in the meeting below stress action, reduce solder the function of contact. Scamper fire (also say to splatter) problem. The element that causes scamper fire is very much, if the cleanness of material is spent, the character of oneself of the purity of material itself, material, and the stability that those who have conclusive effect is laser. Housing surface is raised, stomatic, inner bleb, investigate its reason, advocate if fiber-optic core way is too small,perhaps stimulate light energy to install exorbitant be caused by. Be aimed at the problem that above appears, searching appropriate craft parameter just is the key that solves a problem. CNC Milling
CNC Machining