KR20000040454A - Secondary battery - Google Patents

Abstract

PURPOSE: A second battery is provided to reduce the size of the battery by using a solid electrolyte. CONSTITUTION: An anode material(2) is evaporated on one side surface of a solid electrolyte(1). A cathode material(3) is evaporated on the other side surface of the solid electrolyte(1). A wire material(4) is engaged with the outside of the solid electrolyte(1). A unit battery(5) is manufactured by engaging the wire material with the outside of the solid electrolyte(1). The unit battery(5) is stacked to manufacture a secondary battery(6). According to the secondary battery, the size of the battery is reduced by using a solid electrolyte(1).

Description

Multi-layer thin secondary battery using solid electrolyte

The present invention relates to a multilayer thin secondary battery in which secondary batteries prepared by using a solid electrolyte, a negative electrode, and a positive electrode material are stacked, and then electrically connected in parallel or in series.

Recently, due to the popularization of portable electronic devices, the demand for secondary batteries capable of supplying power to these devices and devices is rapidly increasing, but the lithium secondary batteries currently used are mainly manufactured in bulk type, but the discharge capacity is large. After about 500 charge / discharge cycles, there is a inconvenience to replace due to a decrease in discharge capacity.

In addition, the thin film secondary battery, which is being studied a lot recently, is released as a prototype by depositing a positive electrode, a negative electrode, and an electrolyte on a substrate using a thin film manufacturing method. The semi-permanent advantage is maintained, but since the thickness is small, the discharge capacity is small, so it can be used for micro devices that use low power, but it is difficult to use for portable devices or devices that require a lot of power.

As a related art of the present invention, a lithium manganese oxide thin film electrode for a secondary battery and a method of manufacturing the same (Korean Patent Publication No. 96-019834) can only manufacture a one-dimensional all-solid-state battery by using a substrate. The manufacturing method of a secondary battery (Korean Patent Laid-Open No. 97-013467) is a method of manufacturing an electrode material used in the construction of a battery using a thick film.

However, the present invention can increase the discharge capacity by stacking cells in multiple layers by using a solid electrolyte instead of the substrate, and at the same time reduce the discharge capacity during charging and discharging. It focuses on manufacturing all-solid-state batteries, which are different from the prior art.

Meanwhile, T. Brousse et al. J. of Power source 68, 1997 pp 412-415, et al., Used a solid electrolyte as a substrate, and thinly cut the bulk electrolyte into the anode electrode on both sides. And a cathode electrode were deposited to form an all-solid-state battery cell. In addition, Bates et al. (JB Bates et al. J. of Power source 54 1995, pp 58-62) have fabricated a thin film cell using LiMn ₂ O ₄ thin film as an anode by means of electron-beam evaporation. Announced. However, the present invention provides a secondary battery capable of increasing the discharge capacity or the discharge voltage by not only forming a single solid-state battery by depositing a solid electrolyte but a substrate, and stacking it in multiple layers.

In the present invention, a solid electrolyte is manufactured in a thin thickness to deposit an anode material and a cathode material on both sides to form an electrode, and a metal material that is electrically conductive therein is coated thereon to manufacture a unit cell, and then discharge the battery by stacking the cells in multiple layers. It is to provide a multilayer thin secondary battery that can be used in portable electronic devices, devices that require a lot of power, or electronic cards by increasing the capacity.

1 is a unit cell configuration diagram of the present invention.

2 is a configuration diagram showing a multilayer thin secondary battery model of the present invention.

Explanation of symbols for main parts of the drawings

1: solid electrolyte 2: positive electrode material 3: negative electrode material

4: wiring material 5: unit cell 6: multilayer thin secondary battery

In order to reduce the volume of the multilayer thin secondary battery produced by the present invention, the thickness of the solid electrolyte should be minimized. In the case of a solid electrolyte, since the conductivity of ions is lower than that of a liquid electrolyte or an electrolyte using a polymer, the thickness of the solid electrolyte should be as thin as possible. For this purpose, a conventional thick film technique used to manufacture chip electronic components may be used. Currently, the thick film technique can be used to manufacture electrolytes as thin as 3μm, and when commercialized to manufacture them, it is possible to manufacture secondary batteries that can be used by semi-permanent charging and discharging even with a very small volume.

The multilayer thin secondary battery of the present invention can be obtained as follows.

First, in the manufacture of a solid electrolyte, the solid electrolyte is _{Li 3X Ln 0.67-X TiO 3} , Li X Sr 1-X Ta x Ti 1-X O 3 or Li _2X Sr _{1-2X M-X 0.5} Ta _0.5 O _{3 + x} What can be used in the secondary battery, such as in the form of a bulk in the sintering temperature of 1,300 ~ 1,400 ℃ and cut into a thin thickness of 0.01mm ~ 5mm or to a thickness of 1㎛ ~ 1,000㎛ through the thick film slip casting method I manufacture it thinly

Meanwhile, in the solid electrolyte, the range of x is 0.1x0.67 and Ln may use La, Pr or Nd, and M may use Cr, Fe, Co, Al, Y, Ga, or In.

The positive electrode and the negative electrode material are deposited on both surfaces of the solid electrolyte prepared as described above using a thin film deposition method such as chemical vapor deposition (CVD), sputtering, or sol-gel. In this case, the positive electrode may be a positive electrode material for a lithium secondary battery such as V ₂ O ₅ , LiMn ₂ O ₄ , LiCoO ₂ , LiNiO _2, or TiS _2, and lithium metal, SnO ₂ , hard carbon, or graphite may be used as the negative electrode. have.

After deposition of the electrodes on both sides of the solid electrolyte, a wiring material such as Au, Al, Cu, Ag, Pt, or Cr was deposited on the cathode and the anode with a thickness of 100 μm to 1,000 μm using a thin film or a thick film method, as shown in FIG. 1. Prepare a unit cell such as A multilayer thin secondary battery can be manufactured by stacking unit cells prepared in this way and electrically connecting them in parallel or in series. 2 shows a model of the multilayer thin secondary battery manufactured as described above.

Hereinafter, the present invention will be described by the following examples. However, the technical scope of the present invention is not limited by these.

<Example 1>

Solid electrolyte (1) Li _0.5 La _0.5 TiO ₃ was prepared by the solid phase reaction method at a sintering temperature of 1,300 ° C., and then cut to a thickness of 1 mm. LiMn ₂ O _{4 was used} as the cathode material (2) and lithium metal was used as the anode material (3), and then, the sol-gel method (sol-gel) was deposited on both surfaces of the solid electrolyte to have a thickness of 100 Å. The unit cell 5 was manufactured by sputtering of Au (gold) as the wiring material 4 on the outside where the cathode and the anode were deposited on both sides of the solid electrolyte. Such unit cells were connected in series, stacked in 100 units, and a multilayer thin secondary battery 6 was prepared.

<Example 2>

A solid electrolyte (1) Li _0.6 Sr _0.4 Ta _0.6 Ti _0.4 O ₃ was prepared by the solid-phase reaction method at a sintering temperature of 1,400 ° C., except that it was cut to a thickness of 0.5 mm and aluminum was used as the wiring material (4). The unit cell 5 was manufactured in the same manner as in Example 1. In this way, the unit cells were connected in parallel, stacked in 50 pieces, and a multilayer thin secondary battery 6 was prepared.

The multilayer thin secondary battery manufactured by the present invention can be used as a power source of a portable electronic device or a device that requires a lot of power capacity because of its small volume but a large discharge capacity. In addition, it can be used as a power source by connecting through surface mounting of various devices or circuits, and can be applied to various parts.

Claims (7)

After depositing the positive electrode material (2) on one side of the solid electrolyte (1) and the negative electrode material (3) on the other side and the wiring material (4) on the outside to produce a unit cell (5), the unit cells are laminated A multilayer thin secondary battery using a solid electrolyte, characterized by producing a secondary battery (6). The multilayer thin secondary battery using a solid electrolyte according to claim 1, wherein the cathode material is V ₂ O ₅ , LiMn ₂ O ₄ , LiCoO ₂ , LiNiO ₂ or TiS ₂ . The multilayer thin secondary battery using a solid electrolyte according to claim 1, wherein the negative electrode material is lithium metal, SnO ₂ , hard carbon or graphite. The method of claim 1, wherein the solid electrolyte comprises the _{Li 3X Ln 0.67-X TiO 3} , Li X Sr 1-X Ta x Ti 1-X O 3 or Li _2X Sr _{1-2X M-X 0.5} Ta _0.5 O _{3 + x} Multilayer thin secondary battery using a solid electrolyte, characterized in that used. The multilayer thin secondary battery using a solid electrolyte according to claim 1, wherein the thickness of the cathode material and the cathode material is 100 μm to 100 μm when the solid material is deposited. The multilayer thin secondary battery using a solid electrolyte according to claim 1, wherein the unit cells are stacked in series or in parallel to form a multilayer thin secondary battery. The method of claim 4, wherein the x range of the solid electrolyte is 0.1x0.67, Ln is La, Pr or Nd, M is Cr, Fe, Co, Al, Y, Ga or In using a solid electrolyte, characterized in that Multilayer thin secondary battery.