CN212512529U

CN212512529U - Carbonization furnace for carbonizing lithium ion battery negative electrode material

Info

Publication number: CN212512529U
Application number: CN202020921220.9U
Authority: CN
Inventors: 李鹏
Original assignee: Chenzhou Shanshan New Material Co ltd
Current assignee: Chenzhou Shanshan New Material Co ltd
Priority date: 2020-05-27
Filing date: 2020-05-27
Publication date: 2021-02-09
Anticipated expiration: 2030-05-27

Abstract

The utility model discloses a carbonization furnace for the carbonization treatment of lithium ion battery cathode materials, which comprises a furnace end, a furnace tail, a furnace top, a furnace bottom, a furnace side wall and an auxiliary electric conductor; the furnace head, the furnace tail and the furnace side wall are respectively and fixedly connected with the furnace bottom; the furnace head and the furnace tail are respectively provided with a graphite electrode extending towards the outer wall; the furnace roof is detachable and is provided with an exhaust port; a cubic furnace chamber is formed among the furnace end, the furnace tail, the furnace top, the furnace bottom and the furnace side wall; the auxiliary electric conductors are conductive graphite felts or conductive carbon felts or carbon paper, and a plurality of layers of auxiliary electric conductors are laid in the furnace chamber at intervals up and down; one end of each layer of the auxiliary conductor is in contact connection with the inner wall of the furnace end, and the other end of each layer of the auxiliary conductor is in contact connection with the inner wall of the furnace tail; two ends of each layer of auxiliary conductor are respectively communicated with the corresponding graphite electrodes through the furnace head and the furnace tail; the space between the upper side and the lower side of each layer of the auxiliary conductor is used for filling the material to be carbonized.

Description

Carbonization furnace for carbonizing lithium ion battery negative electrode material

Technical Field

The utility model relates to a retort that is used for lithium ion battery negative pole material carbomorphism to handle.

Background

In the industrial production of carbon cathode materials for lithium ion batteries, the powdery carbon intermediate is often subjected to a heat treatment at 900-1400 ℃, which is commonly referred to as carbonization treatment in the industry, and the corresponding equipment is referred to as a carbonization furnace. After carbonization treatment, part of the carbon-like intermediates can be directly used as a negative electrode material for use or sale, and the other part of the carbon-like intermediates can be used only by graphitization treatment at a higher temperature. The graphitization treatment belongs to a production process with high energy consumption and high cost. The pre-carbonization treatment of the raw materials before graphitization can obviously improve the material loading density, improve the single-furnace yield of the graphitization furnace and reduce the production cost of graphitization treatment.

At present, the carbonization treatment devices for carbon intermediate materials mainly comprising powder or small particles mainly comprise two types: pushed slab kilns and shaft furnaces, both of which have their own advantages, but all suffer from considerable obvious disadvantages.

The pusher kiln is used as a carbonization treatment device of carbon intermediate materials mainly comprising powder or small particles, and has a plurality of defects which are difficult to overcome: 1. the loss of the heating element and the crucible is large, and the operation and maintenance cost of the equipment is large; 2. the carbon intermediate material to be heat treated is indirectly heated, the heating of the push plate and the crucible belongs to ineffective heating, the heat efficiency is low, and the energy consumption is high; 3. the use of a large amount of inert protective gas further increases the production cost; 4. volatile matters generated by the high-volatile matter materials can be deposited on the heating element of the pushed slab kiln at high temperature, so that the heating element is frequently damaged, and the pushed slab kiln cannot carbonize the high-volatile matter materials.

The pit furnace is used as a carbonization treatment device of carbon intermediate materials mainly comprising powder or small particles, and the defects are also obvious: 1. for the carbonization treatment of the lithium ion battery cathode material, each furnace of the largest pit furnace can only load and treat less than 300 kilograms of materials, the equipment productivity is low, and large-scale continuous production cannot be realized; 2. the heating device heats the furnace coil in each production process, which is also invalid heating, and has the disadvantages of large energy waste and low heat efficiency; 3. the furnace coil is repeatedly subjected to rapid cooling and rapid heating, so that the service life of the furnace coil is generally short, and the production cost is further increased.

In recent years, the lithium ion battery industry is rapidly developed, the lithium ion battery is only applied to small digital products such as mobile phones and cameras, and is now expanded to wide fields such as electric automobiles, unmanned aerial vehicles and energy storage power stations, the total social demand of the lithium ion battery on negative electrode materials is increased from thousands of tons every year to tens of thousands of tons every year, and the total social demand is increased by two orders of magnitude. This requires that the corresponding production apparatus must meet the new requirements of mass production on a large scale. The carbonization furnace is one of important devices for producing the cathode material, and has important practical significance for improving the productivity of unit equipment and reducing the energy consumption and the cost.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is to provide a carbonization furnace for lithium ion battery cathode material carbomorphism is handled that cost is lower, the productivity is bigger, the energy consumption is lower, efficiency is higher.

In order to solve the technical problem, the utility model discloses a retort for lithium ion battery negative pole material carbomorphism is handled, its characterized in that: comprises a furnace end, a furnace tail, a furnace top, a furnace bottom, a furnace side wall and an auxiliary conductor; the furnace head, the furnace tail and the furnace side wall are respectively and fixedly connected with the furnace bottom; the furnace head and the furnace tail are respectively provided with a graphite electrode extending towards the outer wall; the furnace roof is detachable and is provided with an exhaust port; a cubic furnace chamber is formed among the furnace end, the furnace tail, the furnace top, the furnace bottom and the furnace side wall; the auxiliary electric conductors are conductive graphite felts or conductive carbon felts or graphite paper, and a plurality of layers of auxiliary electric conductors are laid in the furnace chamber at intervals up and down; one end of each layer of the auxiliary conductor is in contact connection with the inner wall of the furnace end, and the other end of each layer of the auxiliary conductor is in contact connection with the inner wall of the furnace tail; two ends of each layer of auxiliary conductor are respectively communicated with the corresponding graphite electrodes through the furnace head and the furnace tail; the space between the upper side and the lower side of each layer of the auxiliary conductor is used for filling the material to be carbonized.

The auxiliary conductors are in a multi-sheet head-tail lap joint structure.

The furnace bottom and the furnace side wall are both built by insulating refractory bricks and refractory cement.

The furnace head and the furnace tail are both built by graphite bricks or carbon bricks with conductive adhesives.

The furnace top is provided with a plurality of layers, each layer of furnace top is provided with a plurality of refractory fiber felts, and the furnace top is uniformly provided with a plurality of exhaust ports.

And a gas collecting cover is arranged above the gas outlet of the furnace top and is connected with an induced draft system, and the induced draft system is connected with a tail gas purification system.

The temperature field monitoring system and the carbonization furnace are provided with a plurality of temperature measuring points for detecting the temperature of the furnace, the temperature measuring points are provided with platinum-rhodium-platinum thermocouples, and the platinum-rhodium-platinum thermocouples are connected with the temperature field monitoring system.

Adopt the utility model discloses a structure, because auxiliary electric conductor with treat that carbomorphism material successive layer is laid in turn, the carbomorphism material heat conduction is directly treated to auxiliary electric conductor, treat that the carbomorphism material heaies up the back and mainly generate heat through treating carbomorphism material self circular telegram, very big improvement the productivity and the production efficiency of single carbonization stove, production cycle is shorter. Because the auxiliary conductor adopts graphite felt or carbon felt or graphite paper, the total weight of the auxiliary conductor is almost negligible compared with the total weight of the materials, and the invalid heating ratio belonging to the auxiliary conductor is smaller, so the energy consumption is less and the production cost is lower. And the carbon felt or the graphite felt has the characteristics of flexibility, air permeability and the like, can be in closer contact with the material to be carbonized, reduces gaps, improves the capacity, can discharge tail gas more quickly, and can be reused. The cost of the graphite paper is lower.

Drawings

Fig. 1 is a top view of the present invention.

Fig. 2 is a side sectional view of the present invention.

Fig. 3 is an end view of the present invention.

Fig. 4 is a sectional view a-a in fig. 2.

Fig. 5 is a sectional view taken along line B-B in fig. 2.

In the figure: 1-graphite electrode, 2-furnace end, 3-furnace top, 4-exhaust port, 5-furnace side wall, 6-furnace tail, 7-graphite electrode, 8-furnace bottom, 9-material to be carbonized and 10-auxiliary conductor.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings and specific embodiments.

As shown in fig. 1, fig. 2, fig. 3, fig. 4 and fig. 5, the carbonization furnace for carbonizing the negative electrode material of the lithium ion battery of the present invention includes a furnace head, a furnace tail, a furnace top, a furnace bottom, a furnace side wall and an auxiliary electric conductor.

The furnace end, the furnace tail and the furnace side wall are respectively arranged on the furnace bottom and fixedly connected with the furnace bottom. The furnace head and the furnace tail are arranged at two ends of the carbonization furnace, and the furnace side walls are arranged at two sides of the carbonization furnace. The furnace head and the furnace tail are respectively provided with a graphite electrode extending towards the outer wall, and the graphite electrode is a square electrode. The graphite electrode is used for electrifying the carbonization furnace. The furnace top is arranged at the top of the carbonization furnace, the furnace top is detachable and is provided with an exhaust port, the furnace top is made of refractory fiber materials, and the exhaust port is used for exhausting volatile gas generated by heat of materials to be carbonized in the carbonization treatment process. A cubic furnace chamber is formed among the furnace head, the furnace tail, the furnace top, the furnace bottom and the furnace side wall.

The auxiliary electric conductor is a conductive graphite felt or a conductive carbon felt or graphite paper, the conductive graphite felt, the carbon felt and the graphite paper have the performances of conductivity, isolation, heating, flexibility, ventilation and the like, and a plurality of layers are laid in the furnace chamber at intervals up and down. One end of each layer of auxiliary conductor is in contact connection with the inner wall of the furnace end, and the other end of each layer of auxiliary conductor is in contact connection with the inner wall of the furnace tail. Two ends of each layer of auxiliary conductor are respectively communicated with the corresponding graphite electrodes through the furnace head and the furnace tail. The space between the upper side and the lower side of each layer of auxiliary conductor is used for filling the material to be carbonized. The auxiliary conductor can conduct electricity and generate heat, and then the carbonization treatment is carried out on the material to be carbonized.

When the carbonization furnace is used for carbonization treatment, the carbonization furnace comprises four steps of charging, heating, cooling and discharging. When charging, adding the materials to be carbonized layer by layer in the furnace chamber, laying an auxiliary electric conductor on each layer of the materials to be carbonized, respectively contacting and conducting the two ends of the auxiliary electric conductor with the furnace head and the furnace tail, and covering the furnace top to finish charging. During temperature rising, adjustable voltage for carbonization treatment is applied to graphite electrodes at the furnace head and the furnace tail, preferably direct current is selected, so that the auxiliary electric conductor is directly electrified to heat, and the carbonization furnace is heated in an electric heating mode. At the intensification initial stage, the auxiliary conductor heats up the nearly carbomorphism material of treating of both sides about to, the carbomorphism material of treating after the temperature risees, and electric conductivity also promotes, and then self also circular telegram generates heat, and along with thermal transmission, peripheral more carbomorphism material of treating takes place the same transformation, becomes mainly through treating carbomorphism material self circular telegram generate heat and produce the heat to the middle and later stages of intensification. And when the temperature of the material to be carbonized reaches the process requirement, stopping power supply, and finishing temperature rise. When the temperature is reduced, the furnace body and the carbonized materials in the furnace are cooled naturally for a period of time, then the furnace top is removed, the heat dissipation of the furnace body and the carbonized materials in the furnace is accelerated, and when the temperature of the carbonized materials is reduced to meet the discharging condition, the temperature reduction is finished. And when discharging, uncovering the auxiliary electric conductors layer by layer and collecting the carbonized materials layer by layer to finish discharging.

The auxiliary electric conductor is of a multi-sheet head-tail lap joint structure, and is more convenient to repeatedly disassemble, assemble and store.

The furnace bottom and the furnace side wall are both built by insulating refractory bricks and refractory cement, so that electric leakage and heat loss are avoided.

The furnace head and the furnace tail are both built by graphite bricks or carbon bricks with conductive adhesive. Furnace end and stove tail are the conducting wall, and whole wall body all is electrically conductive, is convenient for treat the carbomorphism material with the direct flow direction of electric current, and wider range can improve the circular telegram scope of generating heat of treating the carbomorphism material with treating that the carbomorphism material is direct circular telegram moreover, and then improves the carbomorphism efficiency of treating the carbomorphism material.

The furnace top is provided with a plurality of layers, each layer of furnace top comprises a plurality of refractory fiber felts, the furnace top is uniformly provided with a plurality of exhaust ports, and the exhaust ports are arranged in the fiber felts. The refractory fiber felt is lighter in weight, better in toughness, longer in service life and more convenient to use. The furnace top is provided with a multi-layer refractory fiber felt structure, so that the furnace top is more sealed and insulated, and the furnace top can be conveniently removed layer by layer, thereby being more labor-saving. The furnace top is uniformly provided with a plurality of exhaust ports, so that volatile gas can be exhausted more quickly and more uniformly, carbon deposition is reduced, and damage to the auxiliary electric conductor is reduced.

And a gas collecting cover is arranged above the exhaust port of the furnace top and is connected with an induced draft system, and the induced draft system is connected with a tail gas purification system. In the temperature rising process, volatile gas generated by the material to be carbonized penetrates through the powder gaps and the pores of the auxiliary conductors and is exhausted from an exhaust port at the top of the furnace. And the gas collecting cover above the exhaust port sucks volatile gas under the negative pressure action of the induced draft system, and finally the volatile gas enters the tail gas purification system through the induced draft system for purification treatment. Through setting up gas collection cover, induced air system and tail gas clean system, can reduce air pollution to tail gas clean-up.

The carbonization furnace is provided with a temperature field monitoring system and a plurality of temperature measuring points for detecting the temperature of the furnace, wherein the temperature measuring points are provided with platinum-rhodium-platinum thermocouples, and the platinum-rhodium-platinum thermocouples are connected with the temperature field monitoring system. The platinum-rhodium-platinum thermocouples measure the temperature of the material to be carbonized from a plurality of temperature measuring points, and the temperature field monitoring system collects temperature data collected by the platinum-rhodium-platinum thermocouples to form temperature field data which are used for controlling the voltage and the power and judging whether the process requirements of carbonization heating are met.

Claims

1. The utility model provides a retort that is used for lithium ion battery negative pole material carbomorphism to handle which characterized in that: comprises a furnace end, a furnace tail, a furnace top, a furnace bottom, a furnace side wall and an auxiliary conductor;

the furnace head, the furnace tail and the furnace side wall are respectively and fixedly connected with the furnace bottom; the furnace head and the furnace tail are respectively provided with a graphite electrode extending towards the outer wall; the furnace roof is detachable and is provided with an exhaust port; a cubic furnace chamber is formed among the furnace end, the furnace tail, the furnace top, the furnace bottom and the furnace side wall;

the auxiliary electric conductors are conductive graphite felts or conductive carbon felts or carbon paper, and a plurality of layers of auxiliary electric conductors are laid in the furnace chamber at intervals up and down; one end of each layer of the auxiliary conductor is in contact connection with the inner wall of the furnace end, and the other end of each layer of the auxiliary conductor is in contact connection with the inner wall of the furnace tail; two ends of each layer of auxiliary conductor are respectively communicated with the corresponding graphite electrodes through the furnace head and the furnace tail; the space between the upper side and the lower side of each layer of the auxiliary conductor is used for filling the material to be carbonized.

2. The carbonization furnace for carbonizing the negative electrode material of the lithium ion battery according to claim 1, characterized in that: the auxiliary conductors are in a multi-sheet head-tail lap joint structure.

3. The carbonization furnace for carbonizing the negative electrode material of the lithium ion battery according to claim 1, characterized in that: the furnace bottom and the furnace side wall are both built by insulating refractory bricks and refractory cement.

4. The carbonization furnace for carbonizing the negative electrode material of the lithium ion battery according to claim 1, characterized in that: the furnace head and the furnace tail are both built by graphite bricks or carbon bricks with conductive adhesives.

5. The carbonization furnace for carbonizing the negative electrode material of the lithium ion battery according to claim 1, characterized in that: the furnace top is provided with a plurality of layers, each layer of furnace top is provided with a plurality of refractory fiber felts, and the furnace top is uniformly provided with a plurality of exhaust ports.

6. The carbonization furnace for carbonizing the negative electrode material of the lithium ion battery according to claim 1, characterized in that: and a gas collecting cover is arranged above the gas outlet of the furnace top and is connected with an induced draft system, and the induced draft system is connected with a tail gas purification system.

7. The carbonization furnace for carbonizing the negative electrode material of the lithium ion battery according to claim 1, characterized in that: the carbonization furnace is provided with a temperature field monitoring system and a plurality of temperature measuring points for detecting the temperature of the furnace, wherein the temperature measuring points are provided with platinum-rhodium-platinum thermocouples, and the platinum-rhodium-platinum thermocouples are connected with the temperature field monitoring system.