阅读说明：本技术 一种同时实现对正极材料预脱氧化、对负极材料预锂化的装置及方法 (It is a kind of at the same realize to positive electrode pre-deoxidation, to the device and method of negative electrode material prelithiation ) 是由 许保磊 申昆 李荐 张丹 刘兰英 李娜 于 2019-10-23 设计创作，主要内容包括：一种同时实现对正极材料预脱氧化、对负极材料预锂化的装置及方法,属于锂离子电池领域。本发明通过将富锂层状氧化物正极材料与硅类负极材料匹配,进行充放电处理,将富锂层状氧化物正极材料中多余的锂用于硅类负极材料的预锂化,实现资源再利用。本发明工艺简单,可以同时实现对正极材料的预脱氧和对负极材料的预锂,成本低廉,可规模化生产。(It is a kind of at the same realize to positive electrode pre-deoxidation, to the device and method of negative electrode material prelithiation, belong to field of lithium ion battery.The present invention carries out charge and discharge electric treatment, lithium extra in lithium-rich oxide anode material is used for the prelithiation of silicon class negative electrode material, realize resource reutilization by matching lithium-rich oxide anode material with silicon class negative electrode material.Present invention process is simple, can be realized simultaneously the pre-deoxidation to positive electrode and the pre- lithium to negative electrode material, low in cost, is produced on a large scale.)

1. a kind of realize simultaneously to positive electrode pre-deoxidation, to the device of negative electrode material prelithiation, it is characterised in that: described Device includes working bin, the electrolyte in working bin, protective cover, transmission device and power supply unit；The protective cover is divided into guarantor Shield A and protective cover B, and being connected to respectively with working bin left and right ends, sets that there are two doors, i.e. positive plate entrance on protective cover A With negative electrode tab entrance, set that there are two doors, i.e. positive plate outlet and negative electrode tab outlet on protective cover B；The transmission device point It include that positive plate unreels, positive plate is wound and several positive plate driving cogs for transmission device A and transmission device B, transmission device A Wheel, transmission device B include that negative electrode tab unreels, negative electrode tab is wound and several negative electrode tab transmission gears, transmission device A and transmission device B can be such that positive/negative plate is driven between protective cover and working bin respectively；The power supply unit include charge and discharge power supply, conducting wire and Power supply gear；The power supply gear be divided into power supply gear A and power supply gear B, and by conducting wire respectively with charge and discharge two poles It is connected.

2. one kind according to claim 1 is realized simultaneously to positive electrode pre-deoxidation, to the dress of negative electrode material prelithiation It sets, it is characterised in that: the electrolyte is Li salt/organic solvent electrolyte.

3. one kind according to claim 1 is realized simultaneously to positive electrode pre-deoxidation, to the dress of negative electrode material prelithiation It sets, it is characterised in that: different voltage and electric current can be arranged in the charge and discharge power supply according to demand.

4. one kind according to claim 1 is realized simultaneously to positive electrode pre-deoxidation, to the dress of negative electrode material prelithiation It sets, it is characterised in that: the power supply gear A and power supply gear B is in contact with anode pole piece and cathode pole piece respectively, and not Influence the normal work of transmission device.

5. a kind of realized simultaneously using device as described in claim 1 to positive electrode pre-deoxidation, to the pre- lithium of negative electrode material The method of change, which comprises the following steps:

(1) positive electrode sized mixing, be coated with, prepare anode pole piece, and be wound into a roll；Negative electrode material is sized mixing, is applied Cloth prepares cathode pole piece, and is wound into a roll；

(2) coiled anode pole piece is fed from positive plate entrance, is carried on transmission device A；Certainly by coiled cathode pole piece The charging of negative electrode tab entrance, is carried on transmission device B；

(3) start transmission device A and transmission device B, positive plate volume and negative electrode tab volume unreel respectively, positive and negative electrode pole piece transmitted Enter in electrolyte, stops transmission；

(4) charge and discharge power supply is connected, charge and discharge electric treatment is carried out, after charge and discharge, disconnects charge and discharge power supply；

(5) transmission device A and transmission device B continue to be driven, and transmission distance is respectively L_AAnd L_B, then stop transmission, repeat step (4)；

(6) charge and discharge treated anode pole piece and cathode pole piece are wound at positive plate winding and negative electrode tab winding respectively；

(7) the positive/negative plate volume after winding respectively obtains pre-deoxidation respectively from positive plate outlet and negative electrode tab outlet outflow The cathode pole piece of anode pole piece and prelithiation.

6. one kind according to claim 5 is realized simultaneously to positive electrode pre-deoxidation, to the side of negative electrode material prelithiation Method, it is characterised in that: the positive electrode is lithium-rich oxide anode material.

7. one kind according to claim 5 is realized simultaneously to positive electrode pre-deoxidation, to the side of negative electrode material prelithiation Method, it is characterised in that: the negative electrode material includes Si, SiOx, Si-C compound or SiOx-C compound.

8. one kind according to claim 5 is realized simultaneously to positive electrode pre-deoxidation, to the side of negative electrode material prelithiation Method, it is characterised in that: the charge and discharge electric treatment, which refers to, first charges to positive and negative anodes pole piece, then discharges, charge cutoff voltage 4.6 ~ 4.8V, discharge cut-off voltage are 0.1 ~ 2V, and charging and discharging currents density is 1mA/g ~ 1000mA/g.

9. one kind according to claim 5 is realized simultaneously to positive electrode pre-deoxidation, to the side of negative electrode material prelithiation Method, it is characterised in that: the transmission distance L_ARefer to the length for immersing the anode pole piece of anolyte portion；The transmission away from From L_BRefer to the length for immersing the cathode pole piece of anolyte portion.

10. one kind according to claim 9 is realized simultaneously to positive electrode pre-deoxidation, to the side of negative electrode material prelithiation Method, it is characterised in that: the anode pole piece and cathode pole piece of the immersion anolyte portion can manufacture song in electrolyte Folding, circuitous.

Technical field

The invention belongs to lithium ion battery electrode material fields, and in particular to a kind of to realize simultaneously to positive electrode pre-deoxidation Change, to the device and method of negative electrode material prelithiation.

Background technique

Currently, gradually prohibiting selling with fuel vehicle, lithium ion battery has occupied the mainstream market of electric car, electronic vapour The fast development of vehicle proposes increasingly higher demands to the energy density of lithium ion battery.Traditional positive and negative electrode material is It is not able to satisfy the electric automobile market of high speed development gradually, needs to develop novel lithium ion battery positive and negative electrode material.Rich lithium layer Shape oxide anode material is gradually studied because of advantages such as its high specific discharge capacity (> 250mAh/g), high security, low costs The concern of personnel is one of potential next-generation anode material for lithium-ion batteries.Meanwhile silicon class negative electrode material Yin Qigao is put Electric specific capacity (~ 2000mAh/g, much larger than 400 ~ 600mAh/g of current commercialization negative electrode material), it has also become lithium ion battery Fall over each other the object of research with layout in negative electrode material field.

But lithium-rich oxide anode material is because of its high rate performance is poor, cycle life is low, voltage declines the problems such as dropping limit Its commercial applications is made.In particular, lithium-rich oxide anode material first circle efficiency for charge-discharge is low, a large amount of lithium is not effectively reversible Ground returns to anode, i.e. first circle will cause a large amount of active lithium loss, subsequent to be applied.The part lithium continues to stay in negative In the material of pole, the waste of matched negative electrode material is also led to, and reduces the energy density of full battery.Moreover, rich lithium layer In shape oxide material first circle formation process, part of oxygen precipitation is had, the erosion to electrolyte is caused, it is caused to recycle the longevity Life is further low.Therefore, how to reduce or avoid lithium-rich oxide material first circle lithium resource waste and how Erosion of the oxygen for avoiding first circle from being precipitated to electrolyte, is that commercial applications must solve the problems, such as.

On the other hand, the problems such as first charge-discharge efficiency of silicon class negative electrode material is low, cyclical stability is poor not can solve yet. Silicon class negative electrode material has embedding lithium site abundant, still, after lithium ion insertion, the abjection that some lithium is not effectively reversible, but It is trapped in negative electrode material, becomes " dead " lithium, lose activity.Cause the first charge-discharge efficiency of material low, and lithium is caused to provide A large amount of wastes in source, reduce the energy density of entire full battery indirectly.Therefore, it in order to promote the energy density of full battery, needs Prelithiation is carried out to negative electrode material, improves its head effect.

Prelithiation technique is to solve electrode material head to imitate effective ways that are low, improving full battery energy density.Lithium-ion electric In the formation process of pond, or due to forming consumption of the SEI film to Li, or due to electrode material itself caused by activity Li mistake It is living, it can all cause the capacitance loss of lithium ion battery.Electrode material prelithiation can be supplemented in battery cyclic process for the first time Irreversible capacity loss is conducive to the raising of battery cycle life and the promotion of energy density.

Currently, the method for prelithiation is mainly lithium metal (such as lithium powder, lithium piece) to the pre- lithium of cathode, this method not only wastes lithium Resource, and to operating environment requirements harshness, investment is big, more easily causes security risk, it is urgent to provide a kind of safety, saves, easily The novel prelithiation method of operation.

Summary of the invention

In order to solve, lithium-rich oxide anode material and silicon class negative electrode material first circle efficiency for charge-discharge be low, cycle performance The problems such as poor, the present invention invented a kind of realization simultaneously to positive electrode pre-deoxidation, to the device of negative electrode material prelithiation and Method.

The device and method can be realized simultaneously the pre-deoxidation to positive electrode and the pre- lithium to negative electrode material Change.

The positive electrode is lithium-rich oxide anode material, and the negative electrode material includes Si, SiOx, Si- C compound, SiOx-C compound.

The device includes working bin, the electrolyte in working bin, protective cover, biography to the device of the invention as shown in Figure 1: Dynamic device and power supply unit；The protective cover is divided into protective cover A and protective cover B, and is connected to respectively with working bin left and right ends, It is set on protective cover A there are two door, i.e. positive plate entrance and negative electrode tab entrance, sets that there are two doors, i.e. positive plate on protective cover B Outlet and negative electrode tab outlet；The transmission device is divided into transmission device A and transmission device B, and transmission device A includes that positive plate is put Volume, positive plate winding and several positive plate transmission gears, transmission device B include that negative electrode tab unreels, negative electrode tab is wound and several negative Pole piece transmission gear, transmission device A and transmission device B can be such that positive/negative plate is driven between protective cover and working bin respectively； The power supply unit includes charge and discharge power supply, conducting wire and power supply gear；The power supply gear is divided into power supply gear A and power supply tooth B is taken turns, and is connected respectively with charge and discharge two poles by conducting wire.The electrolyte is Li salt/organic solvent electrolyte.It is described Charge and discharge power supply different voltage and electric current can be set according to demand.The power supply gear A and power supply gear B are respectively and just Pole pole piece and cathode pole piece are in contact, and do not influence the normal work of transmission device.

Specific work steps of the invention is as follows:

(1) positive electrode sized mixing, be coated with etc. and preparing anode pole piece, and being wound into a roll；Negative electrode material is sized mixing, is applied Cloth etc. prepares cathode pole piece, and is wound into a roll；

(2) coiled anode pole piece is fed from positive plate entrance, is carried on transmission device A；Certainly by coiled cathode pole piece The charging of negative electrode tab entrance, is carried on transmission device B；

(3) start transmission device A and transmission device B, positive plate volume and negative electrode tab volume unreel respectively, positive and negative electrode pole piece transmitted Enter in electrolyte, stops transmission；

(4) charge and discharge power supply is connected, charge and discharge electric treatment is carried out, after charge and discharge, disconnects charge and discharge power supply；

(5) transmission device A and transmission device B continue to be driven, and transmission distance is respectively L_AAnd L_B, stop transmission.Repeat step 4；

(6) charge and discharge treated anode pole piece and cathode pole piece are wound at positive plate winding and negative electrode tab winding respectively；

(7) the positive/negative plate volume after winding respectively obtains pre-deoxidation respectively from positive plate outlet and negative electrode tab outlet outflow The cathode pole piece of anode pole piece and prelithiation.

In above-mentioned work step (4), the charge and discharge electric treatment, which refers to, first charges to positive and negative anodes pole piece, then discharges, charging Blanking voltage is 4.6 ~ 4.8V, and discharge cut-off voltage is 0.1 ~ 2V, and charging and discharging currents density is 1mA/g ~ 1000mA/g.

In above-mentioned work step (5), the transmission distance L_ARefer to the length for immersing the anode pole piece of anolyte portion； The transmission distance L_BRefer to the length for immersing the cathode pole piece of anolyte portion；The anode of the immersion anolyte portion The length of pole piece and the length of cathode pole piece, can by manufacturing tortuous, circuitous in electrolyte, to increase length, It improves efficiency.

The invention has the following beneficial effects:

(1) lithium-rich oxide anode material is in first circle charge and discharge process, some lithium is not due to material itself Anode can be returned to, is still trapped in negative electrode material.And silicon class negative electrode material is in first circle charge and discharge process, due to material itself Property, a part of active lithium can be trapped in negative electrode material, lose activity.The present invention is by by lithium-rich oxide anode material Material is matched with silicon class negative electrode material, carries out charge and discharge electric treatment, lithium extra in lithium-rich oxide anode material is used for silicon The prelithiation of class negative electrode material realizes resource reutilization；

(2) lithium-rich oxide anode material avoids erosion of the precipitated oxygen to electrolyte after pre-deoxidationization processing, To greatly prolong its cycle life；

(3) after carrying out prelithiation processing to silicon class negative electrode material, the energy density of its full battery can be greatly improved；

(4) present invention process is simple, can be realized simultaneously the pre-deoxidation to positive electrode and the pre- lithium to negative electrode material, at low cost Honest and clean, a step is completed；

(5) the positive and negative anodes pole piece after process through the invention, obvious reliable, the environmentally friendly, product quality of performance boost It is uniform, reproducible, be produced on a large scale.

Detailed description of the invention

Fig. 1: the device of the invention figure.In figure: 1-working bin；2-electrolyte；3-protective cover A；4-protective cover B；5— Transmission device A；6-transmission device B；7-power supply units；31-positive plate entrances；32-negative electrode tab entrances；41-positive plates go out Mouthful；The outlet of 42-negative electrode tabs；51-positive plates unreel；52-positive plate transmission gears；The winding of 53-positive plates；61-cathode Piece unreels；62-negative electrode tab transmission gears；The winding of 63-negative electrode tabs；71-charge and discharge power supplys；72-power supply gear Bs；73-power supplies Gear A；74-conducting wires.

Fig. 2: Li in the embodiment of the present invention 1_1.2Mn_0.54Ni_0.13Co_0.13O₂C-V(specific capacity-electricity of/graphite full battery Pressure) curve.

Fig. 3: C-V(specific capacity-voltage of SiOx-C/Li button cell in the embodiment of the present invention 1) curve.

Fig. 4: Li in comparative example of the invention_1.2Mn_0.54Ni_0.13Co_0.13O₂C-V(specific capacity-electricity of/graphite full battery Pressure) curve.

Fig. 5: C-V(specific capacity-voltage of SiOx-C/Li button cell in comparative example of the invention) curve.

Fig. 6: Li in comparative example and embodiment 1 of the invention_1.2Mn_0.54Ni_0.13Co_0.13O₂/ graphite full battery is at 0.5C times Cycle performance under rate.

Specific embodiment

Further description of the technical solution of the present invention with reference to the accompanying drawing, and however, it is not limited to this, all to this Inventive technique scheme is modified or equivalent replacement, without departing from the principle and range of technical solution of the present invention, should cover Within the protection scope of the present invention.