Leaf spring compression system design

Patent metadata

Field	Value
Publication number	US-2018233834-A1
Application number	US-201815891277-A
Country	US
Kind code	A1
Filing date	Feb 7, 2018
Priority date	Feb 13, 2017
Publication date	Aug 16, 2018
Grant date	—

Abstract

A leaf spring compression system comprising a mechanical assembly for securing a plurality of leaf springs on a battery cell stack of a flow battery system is disclosed. The cell stack may, comprise: a plurality of cells stacked together to form a flow battery; and a compression system comprising at least two tie rods extending through the plurality of cells clamping a spring acting at opposite ends to compress the cells together, the spring contacting at least two fulcrum elements positioned between the tie rods. In this way, the compression system may exert uniform loading on the battery cell stack, while minimizing deflection of pressure plates attached to the cell stack.

First claim

1 . A cell stack, comprising:
a plurality of cells stacked together to form a flow battery; and a compression system comprising at least two tie rods extending through the plurality of cells clamping a spring acting at opposite ends to compress the cells together, the spring contacting at least two fulcrum elements positioned between the tie rods.

2 . The stack of claim 1 , wherein the fulcrums are movable when the compression is released.

3 . The stack of claim 2 , wherein the spring is a leaf spring comprising one or more leaf spring elements.

4 . The stack of claim 3 , wherein the leaf spring element includes a planar rectangular bar having a length longer than a width longer than a thickness.

5 . The stack of claim 1 , wherein the tie rods are threaded and tightened via rotation about their central longitudinal axis.

6 . The stack of claim 1 , wherein only a pair of fulcrums is mated with only a pair of tie rods, where a plurality of said pairs of rods and fulcrums compresses the stack.

7 . The stack of claim 1 , wherein the fulcrums are positioned between an exterior wall formed by one or more of the plurality of cells and an interior wall of the spring.

8 . The stack of claim 1 , wherein the fulcrums are selected to more evenly distribute load created by the spring across the stack in a direction of a length direction of the spring than if no fulcrums were provided.

9 . The stack of claim 1 , wherein each cell is rectangular in shape and stacked with a shortest edge having a thickness and aligning with other edges of other cells to form a wall of the stack, the tie rods extended through the cells in a direction of the thickness.

10 . The stack of claim 1 , wherein a plurality of singular springs and pairs of tie rods and pairs of fulcrums compress the cell stack, wherein the springs are planar and all lie in a common plane, and the tie rods are all aligned in parallel with each other.

11 . A system, comprising:
a flow battery having a plurality of cells in a cell housing stacked together and a plurality of tie rods extending through the plurality of cells in parallel with each other and clamping a spring acting at an end to compress the cells together, the spring contacting at least two fulcrum elements positioned between the tie rods.

12 . The system of claim 11 , wherein the flow battery further includes plugs inserted through apertures on a downstream face of the cell housing to block the apertures on the cell housing.

13 . The system of claim 11 , wherein the fulcrums are movable when the compression is released, and wherein the spring is a leaf spring comprising one or more leaf spring elements.

14 . The system of claim 13 , wherein the leaf spring element includes a planar rectangular bar having a length longer than a width longer than a thickness.

15 . The system of claim 13 , wherein the tie rods are threaded and tightened via rotation about their central longitudinal axis.

16 . The system of claim 15 , wherein only a pair of fulcrums is mated with only a pair of tie rods, where a plurality of said pairs of rods and fulcrums compresses the stack.

17 . The system of claim 16 , wherein the fulcrums are positioned between an exterior wall formed by one or more of the plurality of cells and an interior wall of the spring.

18 . The system of claim 17 , wherein each cell is rectangular in shape and stacked with a shortest edge having a thickness and aligning with other edges of other cells to form a wall of the stack, the tie rods extended through the cells in a direction of the thickness.

19 . The system of claim 18 , wherein a plurality of singular springs and pairs of tie rods and pairs of fulcrums compress the cell stack, wherein the springs are planar and all lie in a common plane, and the tie rods are all aligned in parallel with each other.

20 . A system, comprising:
a flow battery having a plurality of cells in a cell housing stacked together and a plurality of tie rods extending through the plurality of cells in parallel with each other and clamping a spring acting at an end to compress the cells together, the spring contacting at least two fulcrum elements positioned between the tie rods, wherein the fulcrums are movable when the compression is released, and wherein the spring is a leaf spring comprising one or more leaf spring elements, and wherein a plurality of singular springs and pairs of tie rods and pairs of fulcrums compress the cell stack, wherein the springs are planar and all lie in a common plane, and the tie rods are all aligned in parallel with each other.

Assignees

• Ess Technology Inc

Inventors

• Evans Craig E
• Casey Sean

Classifications

• H01M10/0468

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