Light-detectable solid thin-film secondary battery

• US 7,276,312 B2
• Filed: 12/26/2003
• Issued: 10/02/2007
• Est. Priority Date: 01/14/2003
• Status: Expired due to Fees

• Current Assignee: Japan Science And Technology Agency
• Original Assignee: Japan Science And Technology Agency
• Inventors: Baba, Mamoru
• Primary Examiner(s): Cantelmo; Gregg
• Assistant Examiner(s): Wang; Eugenia
• Application Number:
  US10/542,205
• Publication Number:
  US 20060159986A1
• Time in Patent Office: 1,376 Days
• Field of Search: 429/117, 136/261
• US Class Current: 429/117
• CPC Class Codes: G01J 1/42 using electric radiation detectors optical or mechanical part G01J1/04; by comparison with a reference light or electric value G01J1/10
• CPC Class Codes: H01G 9/2009 Solid electrolytes
• CPC Class Codes: H01M 10/0436 Small-sized flat cells or batteries for portable equipment
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/0562 Solid materials
• CPC Class Codes: H01M 10/488 Cells or batteries combined with indicating means for external visualization of the condition, e.g. by change of colour or of light density
• CPC Class Codes: H01M 14/005 Photoelectrochemical storage cells light sensitive devices H01G9/20, semiconductors sensitive to light H01L31/00
• CPC Class Codes: H01M 2004/021 Physical characteristics, e.g. porosity, surface area
• CPC Class Codes: H01M 4/134 Electrodes based on metals, Si or alloys
• CPC Class Codes: H01M 4/38 of elements or alloys
• CPC Class Codes: H01M 4/386 Silicon or alloys based on silicon
• CPC Class Codes: H01M 6/40 Printed batteries , e.g. thin film batteries
• CPC Class Codes: Y02E 10/542 Dye sensitized solar cells
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

To provide novel devices constituting light detection systems with a simple configuration, a low maintenance cost, a reduced size and weight, and high reliability by integrating light detection components and power supplies.

A photosensitive solid-state thin-film lithium-ion secondary cell including a photosensitive negative-electrode active material layer as a component, wherein extraneous light can be constantly detected by utilizing a change in open-circuit voltage of the cell caused when the extraneous light is incident on the photosensitive negative-electrode active material layer. Lithium ions can be readily received and emitted and light in a broad wavelength range over a near-infrared light range, the entire visible light range, and a near-ultraviolet light range can be detected by utilizing a porous silicon layer having a controlled porosity as the negative-electrode active material layer.

Claims

1. A photosensitive solid-state thin-film lithium-ion secondary cell comprising:

a substrate;

a photosensitive negative-electrode active material layer comprising porous silicon formed on said substrate by anodizing;

a solid electrolyte layer formed on said photosensitive negative-electrode active material;

a positive-electrode active material layer formed on said solid electrolyte layer; and

a current collector layer formed on said positive-electrode active material layer,

wherein the photosensitive solid-state thin-film lithium-ion secondary cell is structured so as to make said photosensitive negative-electrode active material layer receive extraneous light,

wherein extraneous light is to be constantly detected by utilizing a change in open-circuit voltage of the cell caused when the extraneous light is incident on the photosensitive negative-electrode active material layer.

2. The photosensitive solid-state thin-film secondary cell according to claim 1, wherein lithium ions are readily received and emitted and light in a broad wavelength range over a near-infrared light range, the entire visible light range, and a near-ultraviolet light range is detected by utilizing a porous silicon layer having a controlled porosity as the negative-electrode active material layer.

3. The photosensitive solid-state thin-film secondary cell according to claim 1, wherein each of the positive-electrode active material layer and the current collector layer has a film composition and thickness such that the overall transmittance of visible light in the range of 400 nm to 800 nm exceeds 1% on average.

4. The photosensitive solid-state thin-film secondary cell according to claim 1, wherein the photosensitive negative-electrode active material layer comprising the porous silicon is formed by anodizing to dig downward a surface of a silicon wafer substrate.

5. The photosensitive solid-state thin-film secondary cell according to claim 1, wherein a light detection sensitivity is improved by increasing incidence efficiency of light from the positive-electrode side by forming the positive-electrode active material layer disposed as an upper layer in a stripe pattern or in a mesh pattern.

6. The photosensitive solid-state thin-film secondary cell according to claim 1, wherein the photosensitive solid-state thin-film secondary cell is formed together with a electronic circuit of a photodetector on a single silicon substrate.