Energy storage device with encapsulation anchoring

Abstract

Approaches herein provide improved encapsulation of an energy storage device. In one approach, a thin film storage device stack is formed atop a first side of a substrate, and an encapsulant is formed over the thin film storage device stack. A recess formed in the substrate adjacent the thin film storage device stack provides an anchoring point for the encapsulant. In some approaches, the recess is provided partially through a depth of the substrate, and has a geometry to promote physical coupling between the encapsulant and the substrate.

Description

RELATED APPLICATIONS[0001]This Application claims priority to U.S. provisional patent application No. 62 / 322,415, filed Apr. 14, 2016, entitled “Volume Change Accommodating TFE Materials” and incorporated by reference herein in its entirety.FIELD[0002]The present embodiments relate to thin film encapsulation (TFE) technology used to protect active devices and, more particularly, to an energy storage device with an anchored encapsulant.BACKGROUND[0003]Thin film encapsulation (TFE) technology is often employed in devices where the devices are purely electrical devices or electro-optical devices, such as Organic Light Emitting Diodes (OLED). Other than possibly experiencing a generally small global thermal expansion from heat generation during the device operation, these electrical devices and electro-optical devices do not exhibit volume changes during operation, since just electrons and photons are transported within the devices during operation. Such global effects due to global the...

AI Technical Summary

Benefits of technology

[0008]In view of the foregoing, approaches herein provide improved encapsulation of an energy storage device. In one approach, a thin film storage device stack is formed atop a first side of a substrate, and an encapsulant is formed over the thin film storage device stack. Prior to formation of the encapsulant, a recess may be formed in the substrate adjacent the thin film storage device stack, wherein the encapsulant extends into the recess. In some approaches, the recess is provided partially through a depth of the substrate, and has a geometry to promote anchoring of the encapsulant therein.

Problems solved by technology

During a battery cell charge and discharge cycle, the encapsulation layer may lift along cell edges due to a combination of laser edge cutting heat affect zone (HAZ) and poor encapsulation layer adhesion along the cell edges.

Such cell edge delamination leads to the premature introduction of unwanted moisture and gas penetration, resulting in an adverse impact to the battery cell performance.

This leaves minimal cell edge surface area available for lateral encapsulation protection and, as a result, the moisture penetration lateral pathway is short.

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