KR20170098004A

KR20170098004A - Printable battery with high power

Info

Publication number: KR20170098004A
Application number: KR1020160019831A
Authority: KR
Inventors: 김남인; 정명우; 김상윤
Original assignee: (주)플렉스파워
Priority date: 2016-02-19
Filing date: 2016-02-19
Publication date: 2017-08-29
Also published as: KR101782973B1

Abstract

The present invention relates to a printable battery with high power, which is carried out in two steps of a primary printing current collecting layer and a secondary printing current collecting layer in printing the current collector layer to minimize the electrical resistance and to improve the output of the battery by incorporating a metal component having excellent conductivity in the primary printing current collecting layer and to prolong the life of the battery.

Description

[0001] Printable battery with high power [

The present invention relates to a high-output printed battery, and more particularly, to a method for manufacturing a high-output printed battery, which comprises two steps of conducting a primary printing current collector layer and a secondary printing current collector layer to minimize electric resistance, To a high-output printed battery containing an excellent metal component to improve the output of the battery and extend the service life of the battery.

Along with the development of electronic devices, a battery serving as a power source has also been developed in various forms. In recent years, thin sheet type thin type batteries are being developed.

Recently, due to the rapid development of Internet, RFID, smart cards and beauty and medical patch technology, the demand for thin type batteries as a power source of these products is increasing.

In the field of thin type electronic devices, a thin type battery having low durability and mechanical flexibility with a thickness of less than several hundred microns is required, and a battery which is attracting much attention and attention in accordance with such characteristics is a thin type printed battery.

The printed battery can easily produce a large number of cells having a complicated shape, and it is possible to integrate the electronic device and the battery by printing the electrode material directly on the electronic device. A thin printed battery includes an anode, a cathode, an electrolyte, and a current collector layer, as well as a general battery, in which a thin film-like battery is implemented by a printing method.

Thin-film printed cells are structurally divided into face-to-face and coplanar cells. The face-type thin-type battery in which the positive electrode and the negative electrode face each other with the separator interposed therebetween exhibits a relatively good output characteristic as compared with the planar type battery. However, in order to increase the output power of the unit cell, There are many problems such as a decrease in productivity, an increase in manufacturing cost, and a complicated manufacturing process.

On the other hand, in a coplanar battery in which anodes and cathodes coexist on the same plane, a problem of low capacity arises when several unit cells are connected in series in one cell in order to recover low output characteristics.

Most conventional batteries are current collectors that use metal such as sheets or bars. In a battery using a metal current collector, sufficient conductivity is provided so that the discharge speed of the battery is not affected by the current collector.

In thin-film printed batteries, which require all processes to be implemented by printing methods, carbon ink has been used as a current collector layer.

In the thin type battery, the current generated at the discharge is collected in the current collecting layer and flows through the external circuit. Impedance Analysis for Current Flow in a Thin Printed Cell From the experimental results, it was confirmed that the current flowing in the battery is a bottleneck section in the current collecting layer made of carbon, which causes a discharge voltage drop of the battery.

That is, it has been found that it is effective to improve the conductivity of the current collector layer in order to increase the output of the battery. In order to reduce the resistance of the current collecting layer, which is a step of controlling the reaction of the battery, it has been studied to introduce metallic ink into the constituent of the current collector layer.

When the metal ink was introduced into the collector layer instead of the carbon ink, the metal component and the electrode material, especially the anode material, directly reacted electrochemically, so that a voltage drop of the battery and a severe swelling phenomenon due to gas generation were observed. This phenomenon appears to be caused by the overlapping of the manganese dioxide potential, the electrode active material, and the reduction potential of the metal component.

In the present invention, the output of a thin-type printed battery is improved by devising a current-collecting layer having a double-layer structure so as to introduce a metal component having excellent conductivity into the current collector to prevent direct contact with the electrode active material.

Korean Patent Publication No. 10-2007-0004884 Korean Patent Publication No. 10-1051977

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and it is an object of the present invention to provide a method of manufacturing a semiconductor device, which is performed in two steps of a primary printing current collector layer and a secondary printing current- And a printed output layer containing a metal component having excellent conductivity in the printed collector layer to improve the output of the battery and extend the service life of the battery.

The present invention relates to a sheet for use as a substrate whose shape can be varied;

A primary printed current collector layer printed on the sheet and containing a metallic component;

A secondary printing current collector layer printed on the primary printing current collector layer and electrically connected to the primary printing current collector layer;

An electrode layer formed on a part of the secondary printed current collector layer;

A hot melt film formed on an edge of the first electrode layer formed on the electrode layer and serving to prevent the gel electrolyte from leaking out from the outside; And

And a separator layer formed on the first electrode layer on the inner side of the hot melt film to form a gel electrolyte,

The center portion of the sheet between the first electrode layer and the second electrode layer formed on the electrode layer is folded so that the first electrode layer and the second electrode layer abut against each other with the separator interposed therebetween.

The primary printed current collector layer is provided with a primary printed first current collector layer on one side of the sheet and a primary printed second current collector layer spaced laterally from the primary printed first current collector layer .

The primary printed current collector layer contains any one of silver, aluminum, stainless steel, nickel, and copper or a combination thereof.

Wherein the secondary printing current collecting layer comprises a secondary printing first current collecting layer printed on the primary printing first current collecting layer formed on the primary printing collecting layer and a secondary printing printing material Two current collecting layers are provided and the secondary printing primary and secondary collecting layers are printed in a structure covering the entire primary printing primary and secondary collecting layers.

The secondary printed current collector layer is made of carbon.

The electrode layer includes a first electrode layer printed on a part of the secondary printing first current collector layer formed on the secondary printing current collector layer and functioning as an anode and printed on a part of the secondary printing secondary current collector layer to function as a cathode And a second electrode layer.

The first electrode layer contains a manganese dioxide powder, a carbon powder and a binder, and the second electrode layer contains a zinc powder, a carbon powder and a binder.

According to the high-output printed battery of the present invention, in the printing of the current collecting layer, the primary printing current collecting layer and the secondary printing current collecting layer are carried out in two steps to minimize the electrical resistance and also to contain a metal component having excellent conductivity in the primary printing current collecting layer The battery output is improved and the battery life is prolonged.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a plan view of a primary printing current collector layer printed on a sheet of paper according to one embodiment of the present invention. Fig.
2 is a plan view in which a secondary printing current collector layer is printed on a primary printing current collector layer;
3 is a plan view showing the first and second electrode layers formed on the secondary printed current collector layer.
4 is a plan view showing a hot melt film formed on the edge of the first electrode layer.
5 is a plan view showing a separation film formed on the first electrode layer.
6 is a plan view showing a state in which a central portion of a sheet is folded to form a high-
7 is a graph showing impedance measurement values of an embodiment of the present invention.
8 is a graph showing pulse characteristics of an embodiment of the present invention.
FIG. 9 is a plan view of a primary printing current collector layer printed on a sheet of paper according to another embodiment of the present invention. FIG.
10 is a plan view in which a secondary printing current collector layer is printed on a primary printing current collector layer.
11 is a plan view in which first and second electrode layers are formed on a secondary printed current collector layer.
12 is a plan view showing a hot melt film formed on the edges of the first and second electrode layers.
13 is a plan view in which an electrolyte is applied on the first and second electrode layers.
14 is a cross-sectional view of a hot-melt film in which a high-output printed battery is formed by adhering a fleece sheet to an upper portion thereof.
15 is a graph showing impedance measurement values of another embodiment of the present invention.
16 is a graph showing pulse characteristics of another embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the embodiments of the present invention may be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. The shape and the size of the elements in the drawings may be exaggerated for clarity and the same elements are denoted by the same reference numerals in the drawings.

1 to 6, the sheet 100 having a thin and soft nature can be used as a substrate and a wrapping paper of a battery.

However, the present invention is not limited to such a sheet 100, and any designed sheet form for a printed-cell application may be used.

The sheet 100 may be made of various materials such as a polymer or a flexible substrate that can be bent along the shape of a curved object. For example, the sheet 100 may have a thickness of 50 탆 and may be polyethylene naphthalate, polyethylene terephthalate film, etc., and a suitable material may be selected in consideration of moisture barrier property, film flexibility, and the like.

The present invention is characterized in that the current collecting layer of a printed battery is formed by two processes, that is, a primary printing current collecting layer (110) and a secondary printing current collecting layer (210).

In order to realize this, the primary printing first current-collecting layer 111 and the primary printing second current-collecting layer 112 of the primary printing current-collecting layer 110 are formed on the sheet 100 simultaneously with primary printing, The width is formed by printing with 2 mm.

The primary printed current collector layer 110 is a highly conductive layer containing a metal component and serves to reduce the internal resistance of the printed battery.

The shape, width, and thickness of the primary printed first current collector layer 111 and the primary printed second current collector layer 112 are determined experimentally according to the consumed current characteristics of the printed battery, and after printing, Dried.

The primary printing first current collecting layer 111 and the primary printing second current collecting layer 112 contain silver, aluminum, stainless steel, nickel, copper, or a combination thereof. Among them, silver (Ag) Not only is excellent in electrochemical stability, but also exhibits excellent properties in terms of electrical conductivity. In the present invention, the present invention is described based on test results obtained using silver.

A secondary printed current collector layer 210 is printed and formed on the primary printed current collector layer 110.

The secondary printing current collecting layer 210 includes a secondary printing first current collecting layer 211 and a secondary printing second current collecting layer 212. The secondary printing first current collecting layer 211 is a primary printing Is printed on the first current collection layer 111 and the secondary printing second current collection layer 212 is printed on the primary printing second current collection layer 112. [

The secondary printing first current collecting layer 211 and the secondary printing second current collecting layer 212 are made of carbon and have a width of 13.7 mm and a height of 30 mm and are dried for 20 minutes at 150 ° C. or higher by a screen printing method And the thickness after drying is 40 탆.

The primary printed first current collecting layer 111 and the primary printed second current collecting layer 112 are formed so as to be completely covered with the secondary printed first current collecting layer 211 and the secondary printed second current collecting layer 212 And should not be in direct contact with the electrode material to be formed thereafter.

The electrode layer 300 includes a first electrode layer 310 and a second electrode layer 320. The first electrode layer 310 and the second electrode layer 320 are formed on the second printed layer 210. [

The first electrode layer 310 is formed on the secondary printing first current collecting layer 211 and operates as an anode. The constituent material includes a manganese dioxide powder as an electrical active material, a carbon powder, and a binder. 13.7 mm, and a height of 30 mm.

The second electrode layer 320 is formed on the secondary printed collector layer 212 and functions as a cathode. The constituent material includes zinc powder, carbon powder, and binder, which are electrical active materials. The thickness of the second electrode layer 320 is less than 80 μm, , And a height of 30 mm.

The addition of the conductive agent can be eliminated in the cathode according to the required electrical characteristics and the polarities of the first electrode layer 310 and the second electrode layer 320 can be designed to be different from each other.

The hot melt film 400 for sealing the battery is placed on the sheet 100 at the edge of the first electrode layer 310 and adhered by applying heat at about 60 ° C. The width of the hot melt film 400 is 2 mm Respectively.

The hot melt film 400 has a sufficient resistance to an electrolytic solution, selects a material having excellent moisture barrier properties, and usually uses polyethylene as a main component.

A predetermined interval is maintained between the first electrode layer 310 and the hot melt film 400. This provides a space in which the electrolyte can float and the electrolyte is instantaneously heated at 80 ° C. when the battery is sealed. To prevent it.

An isolation layer 500 is formed on the first electrode layer 310 on the inner side of the hot melt film 400 to form a gel-type water-soluble electrolyte.

In order to maintain a uniform amount of the electrolyte in the separator 500, the separator 500 is formed of a doctor blade having a predetermined interval The first electrode layer 310 and the second electrode layer 320 are designed to be larger than the electrode layer 300 with a width of 15.7 mm and a height of 32 mm so that the first electrode layer 310 and the second electrode layer 320 are directly in contact with each other.

A water-soluble electrolytic solution prepared by dissolving 40% by weight of ZnCl ₂ in purified water in purified water of the separator 500 is added to 7% by weight of polyethylene oxide to obtain a viscous property of about 1,000 to 40,000 cps I have.

The first electrode layer 310 and the second electrode layer 320 are formed by sandwiching the separator 500 between the first electrode layer 310 and the second electrode layer 320 and sandwiching the gel electrolyte between the first electrode layer 310 and the second electrode layer 320 Thereby completing a high-output printed battery. At this time, the hot melt film 400 located at the edge of the first electrode layer 310 seals the battery to form a boundary between the inside and the outside of the battery, thereby preventing leakage of the electrolyte.

7 shows impedance data of a high-output printed battery according to an embodiment of the present invention assembled as described above. In Comparative Example 1, on a sheet of paper, a first printed first current-collecting layer 111 and a first printed second current- The flat type flat printed battery was assembled in the same manner as described in the embodiment except that the conductive layer 112 was formed.

In the embodiment of the present invention in which the current collecting layer composed of the double printing of the primary printing current collecting layer and the secondary printing current collecting layer was introduced in the manufacturing process of the high output printed battery, the value of about 20? It has an impedance value of 55Ω.

From this fact, it can be seen that the resistance in the current collecting layer greatly affects the impedance of the whole battery in the thin type printed battery, and it is confirmed that increasing the conductivity of the current collecting layer is effective in improving the impedance.

A test was conducted to see how such impedance difference actually affects the pulse discharge of the battery, and the results are shown in FIG. The pulse condition was set as one cycle with a current of 6 mA for 4 ms and a period of 10 S, and the voltage change of the cell was observed when this cycle was repeated.

In the high output printed battery manufactured under the conditions of the embodiment, the closed voltage was 1.35 V when the peak current value was 6 mA and the open circuit voltage was 1.4 V in the rest state. In contrast, in Comparative Example 1, which was tested under the same pulse condition, the closing voltage was about 0.95 V, and the difference from the open-circuit voltage was about 0.45 V. Which is larger than the difference between the open-circuit voltage and the closed-circuit voltage of 0.05 V in one embodiment, which means that the high-power effect is remarkably improved in one embodiment.

In addition, another embodiment of the present invention will be described, which is applied to a coplanar type printed battery, and more detailed description will be made on the basis of FIGS. 9 to 14.

The sheet 100 having a thin and soft nature can be used as a substrate and a wrapping paper of a battery.

The present invention is characterized in that the current collecting layer of the printed battery is formed by two processes, that is, a primary printing current collecting layer 110 'and a secondary printing current collecting layer 210'.

In order to realize this, the primary printing first current-collecting layer 111 and the primary printing second current-collecting layer 112 of the primary printing current collecting layer 110 'are simultaneously formed on the sheet 100 simultaneously with primary printing , A width of 1 mm and a thickness of 20 m.

The primary printing first current collecting layer 111 and the primary printing second current collecting layer 112 are arranged in a concavo-convex shape and printed in the form of being meshed with each other.

The primary printed current collector layer 110 'is a highly conductive layer containing a metal component and serves to reduce the internal resistance of the printed battery.

A secondary printed current collector layer 210 'is printed and formed on the primary printed current collector layer 110'.

The secondary printed current collector layer 210 'is composed of a secondary printed first current collector layer 211 and a secondary printed second current collector layer 212. The secondary printed first current collector layer 211 has a primary Printed on the first printed current collector layer 111 and the secondary printed second current collector layer 212 printed on the primary printed second current collector layer 112. [

The secondary printing first current collecting layer 211 and the secondary printing second current collecting layer 212 are made of carbon and are manufactured by a screen printing method at a temperature of 150 ° C or higher for 20 minutes, Is 2.4 mm.

The primary printed first current collecting layer 111 and the primary printed second current collecting layer 112 are formed so as to completely cover the secondary printed first current collecting layer 211 and the secondary printed second current collecting layer 212 And should not be in direct contact with the electrode material to be formed thereafter.

An electrode layer 300 'is disposed on the secondary printed current collector layer 210' and the electrode layer 300 'includes a first electrode layer 310 and a second electrode layer 320.

The first electrode layer 310 is formed on a part of the secondary printing first current collecting layer 211 and functions as an anode. The carbon powder and the manganese dioxide powder are mixed to form the first electrode layer 310, To perform gun mixing for 1 hour.

The mixture is mixed with a binder solution to prepare a slurry state, and the binder is mixed with polyethylene oxide, polyvinyl pyrrolidone, and the like.

The prepared slurry is printed on a part of the secondary printing first current collecting layer 211 and dried in a dryer set at 80 캜 for 50 minutes to form a first electrode layer 310. After drying, The thickness is 120 mu m and the width is 2.4 mm. The composition is 90 wt% of manganese dioxide, 5 wt% of carbon black, and 5 wt% of binder.

The second electrode layer 320 is formed on the secondary printed collector layer 212 to act as a cathode. The second electrode layer 320 is mixed with zinc powder, carbon black, and a binder solution dissolved in an organic solvent to prepare a slurry.

The slurry is printed on a part of the secondary printing second current collector layer 212 and dried in a drier set at 60 ° C for 30 minutes to produce a second electrode layer 320. After drying, And a width of 2.4 mm, and the composition thereof is 93% by weight of zinc, 3% by weight of carbon black and 4% by weight of a binder.

The hot melt film 400 'for sealing the battery is placed on the sheet 100 at the edge of the first and second electrode layers 310 and 320 and heated at a temperature of about 60 ° C. to bond the electrolyte. And kept at 2 mm to avoid counting.

The hot melt film 400 'has a sufficient resistance to an electrolytic solution, selects a material having excellent moisture barrier properties, and usually uses polyethylene as a main component.

A predetermined interval is maintained between the first electrode layer 310 and the hot melt film 400 ', which provides a space for the electrolyte to flow and an instantaneous 80 ° C. heat is applied to the battery when sealing the battery. .

A gel-type water-soluble electrolyte 500 'is formed on the first and second electrode layers 310 and 320 on the inner side of the hot melt film 400'.

The electrolyte 500 'is prepared by preparing a water-soluble electrolytic solution containing 60% by weight of water and 40% by weight of ZnCl ₂ and then adding 7% by weight of polyethylene oxide to obtain a sticky ecotype and a viscosity of about 1,000 to 40,000 cps .

The first electrode layer 310 and the second electrode layer 320 are covered by placing the fleece sheet 100 'on the hot melt film 400' and heat of about 80 ° C is applied to the hot melt film 400 ' And the pressure-sensitive adhesive is adhered to each other to complete a high-output printing battery.

15 shows impedance data of a high-output printed battery according to another embodiment of the present invention assembled as described above. In Comparative Example 2, on the sheet paper, a first printed first current-collecting layer 111 and a first printed second current- Flat-type printed cells were fabricated in the same manner as described in the other embodiments, except that the positive electrode 112 was formed.

The impedance of another embodiment of the present invention in which the current collecting layer made of the double printing of the primary printed current collector layer 110 'and the secondary printed current collector layer 210' was introduced during the manufacturing process of the high output printed battery showed a value of about 20? On the other hand, the comparative example 2 showed an impedance value of about 120?, And the other embodiments of the present invention showed an output improvement effect of about 6 times in terms of impedance in comparison with the comparative example 2 of the related art.

A test was conducted to see how such impedance difference actually affects the pulse discharge of the battery, and the results are shown in FIG.

The pulse condition was set as one cycle under the conditions of flowing for 3 ms at a current of 3 mA for 5 ms and at rest for 1 S, and the voltage change of the battery was observed when these cycles were repeated.

In another embodiment of the present invention, when the open-circuit voltage is about 1.4 V and the 3-mA current flows for 5 mS, the closed-circuit voltage is about 1.3 V, and the residual pressure drop is about 0.1 V.

On the other hand, in Comparative Example 2, the open-circuit voltage was 1.4 V and the closed-circuit voltage was 1.0 V, which resulted in a voltage drop of 0.4 V. In addition, the life of the battery in a given pulse condition was about 700 hours in the other examples, but was shortened to 550 hours in the case of Comparative Example 2.

As a result, not only the effect of improving the output of the battery according to the present invention, but also the life of the battery can be greatly increased.

From the above test results, it has been confirmed that, in the case of a thin printed battery, the electric resistance of the current collector layer of the battery greatly affects the impedance of the battery and that it is very effective to reduce the electric resistance to improve the output of the battery.

The present invention can be applied to any compact device on a substrate having a built-in thin-type battery system as well as the pitch of the cosmetics and medicine field. For example, an RFID tag, a tag with a sensor, a smart card, or an electronic device requiring power.

The present invention is not limited to the above-described embodiments and the accompanying drawings. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims, something to do.

100: sheet paper
100 ': Filling sheet
110, 110 ': primary printing collector layer
111: primary printing primary current collecting layer
112: 1st printing 2nd collecting layer
210, 210 ': secondary printing collector layer
211: 2nd printing 1st collecting layer
212: 2nd printing 2nd collecting layer
300, 300 ': electrode layer
310: first electrode layer
320: Second electrode layer
400,400 ': Hot melt film
500:
500 ': gel electrolyte

Claims

A sheet used as a substrate whose shape can be varied;
A primary printed current collector layer printed on the sheet and containing a metallic component;
A secondary printing current collector layer printed on the primary printing current collector layer and electrically connected to the primary printing current collector layer;
An electrode layer formed on a part of the secondary printed current collector layer;
A hot melt film formed on an edge of the first electrode layer formed on the electrode layer and serving to prevent the gel electrolyte from leaking out from the outside;
And a separator layer formed on the first electrode layer on the inner side of the hot melt film to form a gel electrolyte,
Wherein a center portion of the sheet between the first electrode layer and the second electrode layer formed on the electrode layer is folded so that the first electrode layer and the second electrode layer abut against each other with the separator interposed therebetween.

The printing method according to claim 1,
And a first printing second current collecting layer having a primary printing first current collecting layer disposed on one side of the sheet and spaced laterally from the first printing first current collecting layer.

The method of claim 2,
Wherein the primary printed current collector layer contains any one of silver, aluminum, stainless steel, nickel, and copper, or a combination thereof.

The printing method according to claim 1,
A second printing first current collecting layer printed on the first printing first current collecting layer formed on the primary printing collecting layer and a second printing second collecting layer printed on the first printing second collecting layer, Wherein the first and second current collecting layers are printed in a structure covering the entire first and second current collecting layers.

The method of claim 4,
Wherein the secondary printed current collector layer is made of carbon.

2. The electrode according to claim 1,
A second electrode layer printed on a part of the secondary printing first current collector layer formed on the secondary printing current collector layer and having a first electrode layer functioning as an anode and being printed on a part of the secondary printing secondary current collector layer, Wherein the high-power printed battery comprises:

The method of claim 6,
Wherein the first electrode layer contains manganese dioxide powder, carbon powder and a binder, and the second electrode layer contains zinc powder, carbon powder and a binder.

A sheet used as a substrate whose shape can be varied;
A primary printed collector layer disposed on the sheet paper in a concavo-convex shape and containing a metal component;
A secondary printing current collecting layer disposed on the primary printing current collecting layer so as to be meshed with each other and electrically connected to the primary printing current collecting layer;
An electrode layer formed on a part of the secondary printed current collector layer;
A hot melt film formed on an edge of the electrode layer and serving to prevent the gel electrolyte from leaking out from the outside;
A gel-type electrolyte coated on an electrode layer inside the hot melt film;
And a sealing sheet sealed on the top of the hot melt film so as to face the sheet paper.

9. The printing press according to claim 8,
And a first printing second current collecting layer having a primary printing first current collecting layer disposed on one side of the sheet and spaced laterally from the first printing first current collecting layer.

The method of claim 9,
Wherein the primary printed current collector layer contains any one of silver, aluminum, stainless steel, nickel, and copper, or a combination thereof.

9. The printing method according to claim 8,
A second printing first current collecting layer printed on the first printing first current collecting layer formed on the primary printing collecting layer and a second printing second collecting layer printed on the first printing second collecting layer, Wherein the first and second current collecting layers are printed in a structure covering the entire first and second current collecting layers.

The method of claim 11,
Wherein the secondary printed current collector layer is made of carbon.

9. The electrode according to claim 8,
A second electrode layer printed on a part of the secondary printing first current collector layer formed on the secondary printing current collector layer and having a first electrode layer functioning as an anode and being printed on a part of the secondary printing secondary current collector layer, Wherein the high-power printed battery comprises:

14. The method of claim 13,
Wherein the first electrode layer contains manganese dioxide powder, carbon powder and a binder, and the second electrode layer contains zinc powder, carbon powder and a binder.