Self-supporting thin-film battery and method of manufacturing such a battery

• US 10,069,170 B2
• Filed: 02/22/2016
• Issued: 09/04/2018
• Est. Priority Date: 07/13/2015
• Status: Active Grant

• Current Assignee: Stmicroelectronics Tours SAS (STMicroelectronics NV)
• Original Assignee: Stmicroelectronics Tours SAS (STMicroelectronics NV)
• Inventors: Ladroue, Julien, Boufnichel, Mohamed
• Primary Examiner(s): Siddiquee, Muhammad S
• Application Number:
  US15/049,766
• Publication Number:
  US 20170018810A1
• Time in Patent Office: 925 Days
• Field of Search: None
• CPC Class Codes: H01M 10/0436 Small-sized flat cells or batteries for portable equipment
• CPC Class Codes: H01M 10/0585 of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
• CPC Class Codes: H01M 2220/30 Batteries in portable systems, e.g. mobile phone, laptop
• CPC Class Codes: H01M 4/0404 by coating on electrode collectors
• CPC Class Codes: H01M 4/0407 by coating on an electrolyte layer
• CPC Class Codes: H01M 6/40 Printed batteries , e.g. thin film batteries
• 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

A self-supporting thin-film battery is manufacture by forming on the upper surface of a support substrate a vertical active stack having as a lower layer a metal layer having formed therein a first contact terminal of a first polarity of the battery and having formed therein as an upper layer a metal layer having a second contact terminal of a second polarity of the battery. A support film is then bonded to an upper surface of the upper layer. The lower layer is the separated from the substrate by projecting a laser beam through the substrate from a lower surface thereof to impinge on the lower layer.

Claims

1. A method of manufacturing a self-supporting thin-film battery, comprising the steps of:

a) forming on an upper surface of a support substrate a vertical active stack having as a lower layer a metal layer having formed therein a first contact terminal of a first polarity of the battery, a metal cathode collector layer, a cathode layer, an electrolyte layer, an anode layer, an anode collector layer, and as an upper layer a metal layer having formed therein a second contact terminal of a second polarity of the battery;

b) bonding a support film to an upper surface of the upper layer; and

c) separating the lower layer from the support substrate by projecting a laser beam through the support substrate from a lower surface thereof.

2. The method of claim 1, wherein step a) comprises the steps of:

depositing the metal layer of the lower layer on the upper surface of the support substrate;

depositing a first passivation layer on the upper surface of the metal layer of the lower layer; and

forming a first through opening in the first passivation layer opposite a non-peripheral region of the first contact terminal.

3. The method of claim 2, wherein step a) further comprises forming, from an upper surface of the vertical active stack formed by the cathode collector layer the cathode layer, the electrolyte layer, the anode layer and the anode collector layer, a first trench delimiting the contour of the battery, the first trench emerging onto the first passivation layer.

4. The method of claim 3, wherein step a) further comprises the steps of:

depositing a second passivation layer on the upper surface of the vertical active stack formed by the cathode collector layer, the cathode layer, the electrolyte layer, the anode layer and the anode collector layer, as well as on the walls and on the bottom of the first trench;

depositing a protection resin layer above the second passivation layer; and

forming a second through opening in the protection resin and in the second passivation layer opposite a non-peripheral region of the second contact terminal.

5. The method of claim 4, wherein step a) further comprises depositing the metal layer of the upper layer on an upper surface of the protection resin layer and into the second through opening.

6. The method of claim 5, wherein step a) further comprises forming, from the upper surface of the vertical active stack, a second trench delimiting the contour of the battery, the second trench being substantially aligned with the first trench but having a width smaller than that of the first trench and emerging onto the support substrate.

7. The method of claim 1, further comprising:

forming a third contact terminal of the second polarity of the battery, connected by a conductive via to the second contact terminal, in the metal layer of the lower layer, and

forming a fourth contact terminal of the first polarity of the battery, connected by a conductive via to the first contact terminal, in the metal layer of the upper layer.

8. The method of claim 1, wherein the support film is a self-adhesive film.

9. A method, comprising:

forming a lower metal layer on a substrate;

depositing a battery stack on the lower metal layer, said battery stack comprising a metal cathode collector layer, a cathode layer, an electrolyte layer, an anode layer and a metal anode collector layer;

forming an upper metal layer on the battery stack;

applying a laser passing through the substrate to impinge on the lower metal layer and cause separation of the substrate from the lower metal layer.

10. The method of claim 9, further comprising:

dividing the lower metal layer into a first positive contact region and a first negative contact region, said first positive contact region in contact with the metal cathode collector layer;

forming a first electric via for electrically connecting the first negative contact region to the upper metal layer, said upper metal layer in contact with the metal anode collector layer.

11. The method of claim 10, wherein forming the first electric via comprises:

forming a first trench around the battery stack, said first trench not extending through the lower metal layer;

filling the first trench with an insulating material;

forming a second trench in the insulating material filling the first trench, said second trench extending to the first negative contact region of the lower metal layer; and

filling the second trench with metal material to form the first electric via.

12. The method of claim 10, further comprising:

dividing the upper metal layer into a second positive contact region and a second negative contact region, said second negative contact region in contact with the metal anode collector layer;

forming a second electric via for electrically connecting the second positive contact region to the first positive contact region.

13. The method of claim 12, wherein forming the first electric via comprises:

forming a first trench around the battery stack, said first trench not extending through the lower metal layer;

filling the first trench with an insulating material;

forming a second trench in the insulating material filling the first trench, said second trench extending to the lower metal layer; and

filling the second trench with metal material to form the second electric via.

14. The method of claim 9, further comprising:

dividing the upper metal layer into a first positive contact region and a first negative contact region, said first negative contact region in contact with the metal anode collector layer;

forming an electric via for electrically connecting the first positive contact region to the lower metal layer, said lower metal layer in contact with the metal cathode collector layer.

15. The method of claim 14, wherein forming the electric via comprises:

forming a first trench around the battery stack, said first trench not extending through the lower metal layer;

filling the first trench with an insulating material;

forming a second trench in the insulating material filling the first trench, said second trench extending to the lower metal layer; and

filling the second trench with metal material to form the electric via.

16. The method of claim 9, further comprising:

forming a first trench around the battery stack, said first trench not extending through the lower metal layer;

filling the first trench with an insulating material; and

forming a second trench in the insulating material filling the first trench, said second trench extending through both the upper and lower metal layers.