Types and selection of current collectors for lithium ion batteries

lithium ion Battery Convergence body of type and choose
Convergence body yes lithium ion Battery No Lack of part one . it not only Can bear active substance , return Can collect and output electrode active substance produce of current , beneficial to reduce lithium ion Battery of internal resistance , improve Battery of coulomb efficiency , cycle stability and magnification performance . In principle , ideal of lithium ion Battery Convergence body answer satisfy the following condition : ( 1 ) high Conductive Rate ; (2) good of Chemical and electrochemistry stability ; (3) mechanical strength high ; (4) and electrode active substance have good of compatibility and adhesion ; (5) cheap price , easy ; (6) light weight . However , exist actual application process middle , different of fluid collect Material still exist Some question , therefore cannot completely satisfy above many scale Require . if copper exist compare high potential Down easy quilt Oxidation , but Suitable used as negative electrode Convergence body ; aluminum as negative electrode Convergence body of corrosion question More serious , therefore Suitable used as positive electrode Convergence body . at present , copper , aluminum , nickel , Stainless steel wait Metal conductor Material , carbon and composite materials wait semiconductor Material all Available do lithium ion Battery of Convergence body . 1 copper Convergence body copper yes A sort of excellent of Metal conductor , Conductive Rate second only to silver . it have resource Rich , cheap easy , Ductility good wait advantage . but consider arrive copper exist high potential Down easy Oxidation , often quilt used as graphite , silicon , tin and cobalt tin alloy wait negative electrode active substance of Convergence body . common of copper liquid Convergence body have copper foil , Foam copper , Copper network and three dimensional nanometer copper Array wait . 1.1 copper foil Convergence body according to copper foil of Production Process , copper foil again separable for Calendering copper foil and electrolytic copper foil . and electrolytic copper foil compared to , Calendering copper foil have Even high of Conductive Rate and better​​ of extend Effect . electrolytic copper foil Available do No need high bending of lithium ion Battery of negative electrode Convergence body . The results show , Increase copper foil surface Roughness beneficial to improve set electricity body and active substance between of combine strength , reduce active substance and set electricity body between of touch resistance , corresponding land , Battery have better of magnification discharge performance and cycle stability . picture copper foil1.2 Foam copper Collector Foam copper yes A sort of similar sponge of three dimensional network Material , have light weight , strength high , toughness high , specific surface product big wait advantage . although silicon and tin negative electrode active Material have compare high of theory specific volume quantity , quilt think yes lithium ion Battery have future of negative electrode active Material one , but they also exist cycle Discharge process middle body product Variety big , Chalk wait shortcoming , serious Influence Battery performance . The results show , Foam copper Convergence body Can inhibition silicon , tin negative electrode active substance exist Discharge process middle of volume Variety , slow down Chalk Phenomenon , improve Battery of performance . 2 aluminum Convergence body , Although aluminum of Conductivity compare Low and copper compared to , transmission same Power hour , aluminum wire of quality Only need copper wire of half . undoubtedly , aluminum Convergence body of use will help At improve lithium ion Battery of energy density . also , aluminum Compare copper Cheap . lithium ion Battery exist Discharge process middle , aluminum foil set electricity body surface meeting form layer Dense of Oxidation membrane , improve Got it aluminum foil of Corrosion resistance . often quilt used as lithium ion Battery positive electrode of Convergence body . and copper foil Convergence body Same , surface deal with also Can improve aluminum foil of superficiality able . go through DC etching back , aluminum foil surface meeting form honeycomb structure , and positive electrode active substance combine more close , improve Got it lithium ion Battery of electrochemistry performance . but in fact , aluminum set electricity body often because surface passivation membrane of destroy and receive serious corrosion , lithium ion Battery of performance also Followed by reduce . therefore , for improve etching aluminum foil of Corrosion resistance able , need right That surface conduct optimization , form more stable Certainly of passivation membrane . 3 nickel catch receive agent Relatively speaking , nickel yes A sort of price relatively compare Low , conductivity able good , nature relatively stable cheap Metal . acid and base solution . therefore , nickel now that Can used as positive electrode Convergence body , also Can used as negative electrode Convergence body . it now that and positive electrode active substance Phosphoric acid iron lithium match , again and negative electrode active substance Nickel oxide , sulfur , carbon silicon composite materials match . nickel set electricity body of shape usually have Foam nickel and nickel foil Two kinds type . because Foam nickel pores developed , and active substance of Contact surfaces product Larger , reduce Got it active substance and set electricity body between of touch resistance . when use nickel foil as electrode set electricity body hour , along with Charge/ discharge frequency of Increase , active substance easy fall off , Influence Battery of performance . same , surface preprocessing Craftsmanship also Be applicable At nickel foil set electricity body . For example , nickel foil set electricity body surface noodle go through etching back , active substance and set electricity body between of combine strength Significantly Enhance . picture Foam nickel Nickel oxide have structure Stablize , low price , theory specific volume quantity higher advantage . yes A sort of widely used of lithium ion Battery negative electrode active Material . exist this basis superior , use solid state Oxidation method exist Foam nickel surface grow layer Nickel oxide , preparation Got it by Foam nickel for set electricity body of Nickel oxide anode . and nickel foil/ Nickel oxide anode compared to , Foam nickel/ Nickel oxide anode of first discharge specific volume quantity Significantly improve . reason lies in , and two-dimensional Convergence Bulk Compare , three dimensional Convergence body reduce Got it interface polarization Phenomenon , improve Got it Battery of Discharge cycle stability . Phosphoric acid iron lithium quilt think yes power lithium ion ideal of positive electrode active Material Battery because of safety good , raw materials source widely . Will That coating exist Foam nickel Convergence body surface noodle , Can IncreaseLiFePO4 and Foam nickel of Contact surfaces product , reduce interface reaction of Current density , and then improveLiFePO4.4 Stainless steel fluid Convergence body of magnification discharge performance Stainless steel yes refer to Contains nickel of alloy steel , molybdenum , titanium , niobium , copper , iron wait element . have good of conductivity and stability , able resistance Air , steam , water wait weak corrosion medium and acid , base , Salt wait powerful corrosion medium of Chemical corrosion . Stainless steel surface return easy form passivation membrane , Can Protect That surface free from corrosion . at the same time , Stainless steel Can processing have to Compare copper Even Thin , have low cost , Craftsmanship Simple , Can be big scale Production wait advantage . Stainless steel Available do positive electrode or negative electrode of Convergence body . common of Stainless steel collector have Two kinds : stainless steel mesh and Porous Stainless steel . 4.1 stainless steel mesh fluid collector stainless steel mesh texture Dense . as Convergence body hour , That surface quilt electrode active substance pack , basic No and electrolyte direct touch , Not easy occur side effects , beneficial to improve Battery of circularity able . 4.2 Porous Stainless steel fluid Convergence body for Take advantage of active substance , improve electrode of discharge specific volume quantity , A sort of Simple efficient of method yes use Porous Convergence body . 5 carbon Convergence body when carbon Material used as positive electrode or negative electrode Convergence body hour , electrolyte right Metal Convergence body of corrosion Can avoid , and have resource Rich , easy processing , Resistivity Low , right environment none harm , low price wait advantage . carbon fiber cloth because of good of performance Can be done for Flexible lithium ion Battery of Convergence body . Flexibility , conductivity and electrochemistry stability . carbon nanotubes yes Other A sort of carbon Convergence body . and Metal Convergence Bulk Compare , That obvious of Advantage lies in light weight , Can Greatly improve Battery of energy density . 6 complex Convergence body Apart from copper Convergence body , aluminum Convergence body , nickel Convergence body , Stainless steel wait single Convergence body receive widely focus on outside Convergence body and carbon Convergence body , in recent years , complex Convergence body also cause Got it scholar them of Research interest , like Conductive Resin , carbon Bag aluminum foil and titanium nickel shape memory alloy wait . 6.1 Conductive Resin Convergence body polyethylene ( PE ) and Phenolic Resin ( PF ) fluid Convergence body Depend on Conductive filler and polymer Resin matrix composition . byPE andPF for matrix Material , and Conductive filler ( graphite and carbon black ) Mixed system Prepare complex fluid Convergence body , and Research That physics and Chemistry able . graphite ene yes Depend on carbon atomSP2 miscellaneous Transformation become of A sort of unique of two-dimensional carbon Function Material . it have super high of Conductive Rate , specific surface product and mechanical strength wait Many advantage . it not only Can replace graphite as lithium ion Battery of positive electrode active Material , return Can as fluid Convergence body Material . 6.2 titanium nickel shape memory alloy fluid Convergence body titanium nickel shape memory alloy yes Depend on nickel and titanium composition of Binary alloy . along with outside world temperature or pressure of Variety , Two kinds different of crystal Mutually Can mutual Convert . Ti Ni shape memory alloy Can pass Change That Phase state Come inhibition active substance exist Discharge process middle of volume Variety , improve Battery of cycle life . 6.3 carbon Bag aluminum foil set electricity body carbon/ aluminum foil set electricity body yes A sort of complex set electricity body , surface coating Containing carbon composite materials aluminum foil surface have layer . carbon layer Depend on carbon fiber and through Dispersant deal with of Conductive carbon black particles composition , Can and aluminum foil tightly integrated , improve electrode of conductivity able and Corrosion resistance . Convergence body yes lithium ion Battery middle heaviest want of part one . have bear electrode active substance and collect output current wait Various Function . different Material , different Production Process preparation of Convergence body of performance different , right lithium ion Battery of effect also different .