Background technology
The advantages such as energy density is high owing to having for lithium ion battery, good cycle, operating voltage are high, memory-less effect, become one of secondary cell of the widest model of application.Lithium battery is made up of main 5 partial component: positive electrode, negative material, barrier film, electrolyte and accessory part.Anodal general select relative lithium current potential to be greater than 3V and at the heavily stable lithium intercalation compound of air, as LiCoO
2, LiNiO
2, LiMnO
2deng; Negative material selects current potential to approach as far as possible the embedded lithium compound of lithium current potential, as lithium--and carbon intercalation compound LixC
6; Electrolyte mostly is and is dissolved with lithium salts LiPF
6, LiAsF
6deng organic solvent; Diaphragm material is generally PP, PE etc.; Accessory part comprises shell, cover plate, lug, insulating trip etc.
Lithium ion battery is divided into stacked and takeup type.What column lithium ion battery adopted is coiled manufacturing process, its main feature is: on the positive/negative plate of intermittently coating, reserve in advance the welding position of lug, then the city utmost point group of reeling together after with barrier film, positive and negative plate being separated again after soldering polar ear enters shell encapsulation.
Column lithium ion battery conventionally has the capacity of 2000-2400mAh and is generally installed in notebook, digital camera and the video camera and portable power tool that consumes a large amount of electric energy.Along with the development of technology, various machinery equipments constantly tend to miniaturization, intellectuality, and this just requires the Fabrication of High Specific Capacitance quantification more of its power supply.In addition, the field such as electric automobile requires motive-power battery must have height ratio capacity, low cost and high security.Traditional cylindrical lithium ion battery generally can not meet powerful electric discharge requirement like this.
The performance of lithium ion battery and the performance of battery material are closely related, the therefore development course of lithium ion battery the updating and innovating of battery material that invariably accompany.All the time, the emphasis of Study on Li-ion batteries using mainly concentrates on positive electrode, negative material and electrolyte aspect.Research shows, the every lifting 50% of specific capacity of positive electrode, and the capacity of battery can improve 28%, and the capacity of negative material improves 50%, and the capacity of battery only improves 13%; Positive electrode cost accounts for 40% left and right of lithium ion battery total cost; Therefore the development that, positive electrode is is restricting price and the chemical property of lithium ion battery.Find high-performance, positive electrode is the general trend of current World Battery industry development cheaply.
Numerous domestic researcher is doing a large amount of research aspect the modification of anode material for lithium-ion batteries.Patent CN200910214418.1 discloses a kind of high-rate cylindrical lithium ion battery of battery with anode of modified LiMn2O4, adopt the modified lithium manganate of doping nickel, and optimized on battery structure, make the present invention can meet existing electricity consumption product to the powerful electric discharge requirement of battery, can reach again the requirement of high security; Chinese patent 201110027246.4 discloses a kind of preparation method who mixes indium manganate cathode material for lithium, and the lithium ion battery that adopts this positive electrode to prepare has better cycle performance, and battery storage self discharge reduces, and capacitance loss is corresponding reducing also.Although all having adopted the mode of modification or doping ion to reach, foregoing invention patent changes anodal performance, from all not improving in essence the capacity of lithium ion battery.And for cobalt acid lithium (LiCoO
2) the positive electrode modification research that improves its battery capacity is but rare for rarely seen.As everyone knows, cobalt acid lithium (LiCoO
2) be one of positive electrode that lithium ion battery is conventional.LiCoO
2the embedding lithium current potential of positive electrode is high, and theoretical capacity reaches 274mAh/g, but in actual cycle process, in the time having the lithium ion that exceedes half to deviate from, there is serious degeneration in the capacity of material, its layer structure is tended to subside, and makes actual capacity be no more than 150mAh/g.
Therefore the capacity that, how to promote the positive electrode of column lithium ion battery has become one of problem that urgently will solve.
Summary of the invention
The object of the invention is to overcome above-mentioned technical problem, a kind of retention of charge is strong, storage capacity is large lithium ion anode material and column lithium ion battery and preparation method are provided.
The technical solution adopted in the present invention is as follows:
On the one hand, the embodiment of the present invention provides a kind of column lithium ion battery, described column lithium ion battery comprises: positive plate, negative plate, electrolyte, barrier film, metal-back, be coiled into column type volume core according to the sequential volume of barrier film/positive plate/barrier film/negative plate, described volume core outer wrap cylindrical metal shell, wherein said positive plate comprises positive electrode, and described positive electrode is cobalt acid lithium (LiCoO
2) material, at cobalt acid lithium (LiCoO
2) in material, the compound of doped indium.Element indium of the present invention is 0.005%~6% at the mass fraction of mixing in indium cobalt acid lithium.
As technique scheme preferably, element indium is 0.01%~1.6% at the mass fraction of mixing in indium cobalt acid lithium.
As technique scheme preferably, the compound of described indium, includes but not limited to indium oxide [In
2o
3], indium hydroxide [In (OH)
3], one or two or more kinds mixing in indium phosphide [InP].
On the other hand, the embodiment of the present invention provides a kind of column lithium ion battery manufacture method, and described column lithium ion battery manufacture method comprises:
Indium lithium cobaltate cathode material is mixed in preparation;
Prepare positive plate;
Prepare battery cathode sheet and battery assembled formation.
The described positive electrode step of preparing comprises:
At cobalt acid lithium (LiCoO
2) compound of additional indium in powder;
Grind batch mixing taking alcohol, agate ball as medium, material: ball: alcohol ratio is 1: 2: 1.5 (mass ratio), puts into star ball grinder, grind batch mixing after 30 minutes, put into microwave oven and dry, make and mix indium lithium cobaltate cathode material.
As technique scheme preferably, element indium is 0.005%~6% at the mass fraction of mixing in indium cobalt acid lithium.
As technique scheme preferably, the compound of described indium, comprises indium oxide [In
2o
3], inidum chloride [In
2cl
3], indium hydroxide [In (OH)
3], one or two or more kinds mixing in indium phosphide [InP].
As technique scheme preferably, the compound of described indium add mode, can adopt cobalt acid lithium to be uniformly mixed with indium compound, also can prepare the sour lithium (LiCoO of cobalt
2) process in add the compound of indium, the present invention preferably to adopt to prepare cobalt acid lithium (LiCoO
2) process in add the compound of indium.
The described positive plate step of preparing comprises:
By positive electrode, acetylene carbon black is conductive agent, poly-inclined to one side tetrafluoroethene (PVDF) adhesive, and three's ratio of 94: 3.5: 2.5 is by mass percentage made slurry, is evenly coated on the aluminium foil that 20 μ m are thick and makes positive plate.
Describedly prepare battery cathode sheet and battery assembled formation step comprises:
Negative electrode active material small particle diameter Delanium, acetylene carbon black, poly-inclined to one side tetrafluoroethene (PVDF) adhesive are mixed in the ratio of 94: 3.5: 2.5, add appropriate NMP to mix well into pasty state, be evenly coated on the Copper Foil that 15 μ m are thick and make negative plate.Then adopt the porous barrier film that 20 μ m are thick, be coiled into column type volume core by the sequential volume of barrier film/positive pole/barrier film/negative pole.Above-mentioned volume core is put into cylindrical metal shell, after laser welding, inject after electrolyte sealing and make and add indium cylindrical lithium-ion power battery.
Compared with prior art, the invention has the advantages that: what the invention provides that a kind of product composition and structure be obviously different from existing cobalt acid lithium product mixes indium cobalt acid lithium battery, due to adding of phosphide element, configuration of surface and the internal structure of cobalt acid lithium are improved, improve the activity of cobalt acid lithium, made the specific capacity of mixing indium cobalt acid lithium and have as anode material for lithium-ion batteries better electric conductivity and Geng Gao after modification.In addition, also reduce the internal resistance of lithium ion battery, improved the security performance of circulation volume conservation rate and battery.The compound addition 0.005wt%~6wt% of indium, for experiment gained of the present invention is optimized interval, not mathematics exact value; But addition is too low, improve effect obvious not, addition is too high, can cause again positive pole material of lithium cobalt acid (LiCoO
2) active decline, performance produces and worsens, and causes capacity of lithium ion battery to reduce.
After doped indium element, improve cobalt acid lithium (LiCoO
2) electric conductivity of material, thereby reducing internal resistance, capacity also improves greatly, and the capacitance of the column lithium ion battery of preparing than tradition can increase by 10%~20% capacity, and the security performance of battery has also obtained large increase.
Embodiment
In order to make, the object, technical solutions and advantages of the present invention are clearer, embodiment of the present invention is described further in detail below.
embodiment 1
At cobalt acid lithium (LiCoO
2) additional 0.0121wt% indium oxide in powder, now element indium is 0.005% at the mass fraction of mixing in indium cobalt acid lithium, the dispersant of 0.05wt%, grind batch mixing taking alcohol, agate ball as medium, material: ball: alcohol ratio is 1: 2: 1.5 (mass ratio), puts into star ball grinder, ground batch mixing after 30 minutes, put into microwave oven and dry, make and mix indium lithium cobaltate cathode material.By positive electrode, acetylene carbon black is conductive agent, poly-inclined to one side tetrafluoroethene (PVDF) adhesive, and three's ratio of 94: 3.5: 2.5 is by mass percentage made slurry, is evenly coated on the aluminium foil that 20 μ m are thick and makes positive plate.
Negative electrode active material small particle diameter Delanium, acetylene carbon black, poly-inclined to one side tetrafluoroethene (PVDF) adhesive are mixed in the ratio of 94: 3.5: 2.5, add appropriate NMP to mix well into pasty state, be evenly coated on the Copper Foil that 15 μ m are thick and make negative pole.Then adopt the porous barrier film that 20 μ m are thick, be coiled into column type volume core by the sequential volume of barrier film/positive pole/barrier film/negative pole.Above-mentioned volume core is put into cylindrical metal shell, after laser welding, inject after electrolyte sealing and make and add indium cylindrical lithium-ion power battery.
embodiment 2
At cobalt acid lithium (LiCoO
2) additional 14.49% indium oxide in powder, now element indium is 6% at the mass fraction of mixing in indium cobalt acid lithium, grind batch mixing taking alcohol, agate ball as medium, material: ball: alcohol ratio is 1: 2: 1.5 (mass ratio), put into star ball grinder, grind batch mixing after 30 minutes, put into microwave oven and dry, make and mix indium lithium cobaltate cathode material.
Prepare positive plate, negative plate and battery assembled formation step with embodiment 1.
embodiment 3
At cobalt acid lithium (LiCoO
2) additional 0.024% indium oxide in powder, now element indium is 0.01% at the mass fraction of mixing in indium cobalt acid lithium, grind batch mixing taking alcohol, agate ball as medium, material: ball: alcohol ratio is 1: 2: 1.5 (mass ratio), put into star ball grinder, grind batch mixing after 30 minutes, put into microwave oven and dry, make and mix indium lithium cobaltate cathode material.
Prepare positive plate, negative plate and battery assembled formation step with embodiment 1.
embodiment 4
At cobalt acid lithium (LiCoO
2) additional 3.86wt% indium oxide in powder, now element indium is 1.6% at the mass fraction of mixing in indium cobalt acid lithium, grind batch mixing taking alcohol, agate ball as medium, material: ball: alcohol ratio is 1: 2: 1.5 (mass ratio), put into star ball grinder, grind batch mixing after 30 minutes, put into microwave oven and dry, make and mix indium lithium cobaltate cathode material.
Prepare positive plate, negative plate and battery assembled formation step with embodiment 1.
embodiment 5
At cobalt acid lithium (LiCoO
2) additional 0.0073wt% indium hydroxide in powder, now element indium is 0.005% at the mass fraction of mixing in indium cobalt acid lithium, grind batch mixing taking alcohol, agate ball as medium, material: ball: alcohol ratio is 1: 2: 1.5 (mass ratio), put into star ball grinder, grind batch mixing after 30 minutes, put into microwave oven and dry, make and mix indium lithium cobaltate cathode material.
Prepare positive plate, negative plate and battery assembled formation step with embodiment 1.
embodiment 6
At cobalt acid lithium (LiCoO
2) additional 8.73wt% indium hydroxide in powder, now element indium is 6% at the mass fraction of mixing in indium cobalt acid lithium, preparation method is with embodiment 1.
embodiment 7
At cobalt acid lithium (LiCoO
2) additional 0.015wt% indium hydroxide in powder, now element indium is 0.01% at the mass fraction of mixing in indium cobalt acid lithium, preparation method is with embodiment 1.
embodiment 8
At cobalt acid lithium (LiCoO
2) additional 2.32wt% indium hydroxide in powder, now element indium is 1.6% at the mass fraction of mixing in indium cobalt acid lithium, preparation method is with embodiment 1.
embodiment 9
At cobalt acid lithium (LiCoO
2) additional 0.0072wt% indium phosphide in powder, now element indium is 0.005% at the mass fraction of mixing in indium cobalt acid lithium, preparation method is with embodiment 1.
embodiment 10
At cobalt acid lithium (LiCoO
2) additional 8.7wt% indium phosphide in powder, now element indium is 6% at the mass fraction of mixing in indium cobalt acid lithium, preparation method is with embodiment 1.
embodiment 11
At cobalt acid lithium (LiCoO
2) additional 0.014wt% indium phosphide in powder, now element indium is 0.01% at the mass fraction of mixing in indium cobalt acid lithium, preparation method is with embodiment 1.
embodiment 12
At cobalt acid lithium (LiCoO
2) additional 2.32wt% indium phosphide in powder, now element indium is 1.6% at the mass fraction of mixing in indium cobalt acid lithium, preparation method is with embodiment 1.
For embody more highlightedly technical scheme of the present invention prepared mix indium cobalt acid lithium ion battery at the outstanding advantage aspect battery capacity and security performance, those skilled in the art adopt again traditional handicraft to prepare the cobalt acid lithium (LiCoO of the indium that undopes
2) lithium ion battery as a comparative example 1,2,3.
Comparative example 1
By cobalt acid lithium (LiCoO
2): acetylene carbon black conductive agent: poly-inclined to one side tetrafluoroethene (PVDF) adhesive, ratio was made slurry in 94: 3.5: 2.5 by mass percentage, was evenly coated on the aluminium foil that 20 μ m are thick and made positive plate.Negative electrode active material small particle diameter Delanium, acetylene carbon black, poly-inclined to one side tetrafluoroethene (PVDF) adhesive are mixed in the ratio of 94: 3.5: 2.5, add appropriate NMP to mix well into pasty state, be evenly coated on the Copper Foil that 15 μ m are thick and make negative pole.Then adopt the porous barrier film that 20 μ m are thick, be coiled into column type volume core by the sequential volume of barrier film/positive pole/barrier film/negative pole.Above-mentioned volume core is put into cylindrical metal shell, seal after injecting electrolyte after laser welding, make and add indium cylindrical lithium-ion power battery.
Comparative example 2
By cobalt acid lithium (LiCoO
2): acetylene carbon black conductive agent: poly-inclined to one side tetrafluoroethene (PVDF) adhesive, ratio was made slurry in 93: 4: 3 by mass percentage, was evenly coated on the aluminium foil that 20 μ m are thick and made positive plate.Other step is with comparative example 1.
Comparative example 3
By cobalt acid lithium (LiCoO
2): acetylene carbon black conductive agent: poly-inclined to one side tetrafluoroethene (PVDF) adhesive, ratio was made slurry in 95: 2: 2 by mass percentage, was evenly coated on the aluminium foil that 20 μ m are thick and made positive plate.Other step is with comparative example 1.
For the better technical solution of the present invention that embodies is at the technique effect obtaining aspect battery capacity lifting, those skilled in the art adopt again identical technique, respectively at cobalt acid lithium (LiCoO
2) and LiMn2O4 (LiMnO
2) in the phosphide element of doping 0.12wt%, prepared the embodiment 13 of the cobalt acid lithium ion battery of mixing indium and mixed the manganate lithium ion battery comparative example 4 of indium.
embodiment 13
At cobalt acid lithium (LiCoO
2) additional 0.29wt% indium oxide in powder, now element indium is 0.12% at the mass fraction of mixing in indium cobalt acid lithium, grind batch mixing taking alcohol, agate ball as medium, material: ball: alcohol ratio is 1: 2: 1.5 (mass ratio), put into star ball grinder, grind batch mixing after 30 minutes, put into microwave oven and dry, make and mix indium lithium cobaltate cathode material.
Prepare positive plate, negative plate and battery assembled formation step with embodiment 1.
Comparative example 4
At LiMn2O4 (LiMnO
2) additional 0.29wt% indium oxide in powder, now element indium is 0.12% at the mass fraction of mixing in indium LiMn2O4, grind batch mixing taking alcohol, agate ball as medium, material: ball: alcohol ratio is 1: 2: 1.5 (mass ratio), put into star ball grinder, grind batch mixing after 30 minutes, put into microwave oven and dry, make and mix indium manganate cathode material for lithium.
Prepare positive plate, negative plate and battery assembled formation step with embodiment 1.
The electrolyte that above-described embodiment battery uses is the electrolyte of resistance to overshoot.
Battery performance test:
To changing into and reprocessing with two kinds of column lithium ion batteries that said method is made, and adopt the AC resistance tester of 1000HZ to measure the internal resistance of battery, then carry out cycle performance test and security performance test.
Table 1 is the battery performance comparison of embodiment of the present invention 1-12 and comparative example 1-3, in table, data show, the battery capacity that the present invention makes is than high 20% left and right of the battery capacity of traditional design, and internal resistance only has the traditional design internal resistance of cell 35% left and right, circulation volume conservation rate is also better than conventional batteries, and security performance is also higher than conventional batteries.
Table 1 embodiment of the present invention 1-12 and comparative example 1-3 battery performance comparison sheet
As can be known from the above table: due to adding of phosphide element, improved configuration of surface and the internal structure of cobalt acid lithium, improved the activity of cobalt acid lithium, made the specific capacity of mixing indium cobalt acid lithium and have as anode material for lithium-ion batteries better electric conductivity and Geng Gao after modification.In addition, also reduce the internal resistance of lithium ion battery, improved the security performance of circulation volume conservation rate and battery.
Table 2 is battery performance comparisons of the embodiment of the present invention 13 and comparative example 4, in table, data show, also high 10% left and right of manganate lithium ion battery capacity that the cobalt acid lithium ion battery Capacity Ratio of mixing indium of the present invention's making is mixed indium, and manganate lithium ion battery internal resistance 70% left and right of indium is only mixed in internal resistance, circulation volume conservation rate is suitable, but security performance is also higher than the manganate lithium ion battery of mixing indium.
Table 2 embodiment of the present invention 13 and comparative example 4 battery performance comparison sheets
Above-described embodiment is the more preferably one of embodiment of the present invention, within the common variation that those skilled in the art carries out within the scope of technical solution of the present invention and replacement all should be included in protection scope of the present invention.