Low energy activation fault tolerant battery cell bypass device and system

Patent metadata

Field	Value
Publication number	US-2016308254-A1
Application number	US-201514689607-A
Country	US
Kind code	A1
Filing date	Apr 17, 2015
Priority date	Apr 17, 2015
Publication date	Oct 20, 2016
Grant date	—

Abstract

A low energy activation, fault tolerant, battery system includes an electrical storage cell having a positive terminal and a negative terminal. The electrical storage cell is provided with a normally open bypass circuit path that is closed in the event of an overdischarged, or open-circuit failure of, the electrical storage cell. The bypass circuit path includes a first electrical conductor connected to the negative terminal of the electrical storage cell, a second electrical conductor connected to the positive terminal of the electrical storage cell, and a shorting gap between the first electrical conductor and the second electrical conductor. The first and second electrical conductors and a non-conductive carrier at least partially enclose a heat source activatable upon the occurrence of the failed cell, a mass of a meltable material that is heated by the heat source, a plunger having an electrically conductive face, and a spring that is positioned to force the plunger into the mass of the meltable material when it is at least partially molten. The heat source includes two diodes connected in electrical series, each of which is operable to melt at least a portion of the mass of the meltable material. When the spring forces the plunger into the meltable material, the electrically conductive face of the plunger head physically contacts the first and second electrical conductors to eliminate the shorting gap so that the first electrical conductor is in electrical communication with the second electrical conductor.

First claim

What is claimed is:

1 . A battery system comprising:
an electrical storage cell having a positive terminal and a negative terminal; a normally open bypass circuit path comprising:
a first electrical conductor connected to the negative terminal of the electrical storage cell;
a second electrical conductor connected to the positive terminal of the electrical storage cell; and
a shorting gap between the first electrical conductor and the second electrical conductor;
a mass of meltable material; first and second diodes electrically connected in series,
each of the first and second diodes having a cathode and an anode, the anode of the first diode being electrically connected to the negative terminal of the electrical storage cell and the cathode of the second diode being electrically connected to the positive terminal of the electrical storage cell,
each of the first and second diodes being heat source activatable upon the occurrence of a voltage reversal of the electrical storage cell, and
each of the first and second diodes having a sufficient heat output to melt the meltable material;
a plunger comprising a head and a stem, the stem extending towards the meltable material and the head having an electrically conductive face; and a biasing mechanism positioned to force the plunger into the mass of the meltable material, when the mass of the meltable material is at least partially molten, such that the conductive face of the head of the plunger physically contacts the first electrical conductor and the second electrical conductor to close the shorting gap and bridge electrical communication between the first conductor and the second electrical conductor.

2 . The battery system of claim 1 further comprising an electrically non-conductive carrier for at least partially enclosing the meltable material, plunger, and biasing mechanism.

3 . The battery system of claim 1 wherein the biasing mechanism comprises a spring that is positioned to push the plunger into the meltable material when the meltable material is at least partially molten.

4 . The battery system of claim 1 further comprising an electrically non-conductive spacer that separates the first and second diodes from the meltable material.

5 . The battery system of claim 1 wherein the meltable material is a wax.

6 . The battery system of claim 5 wherein the meltable material is paraffin.

7 . The battery system of claim 1 wherein the meltable material has a melting point of no more than about 128 degrees F.

8 . The battery system of claim 1 further comprising a second electrical storage cell in an electrical series relationship.

9 . A battery system comprising:
an electrical storage cell having a positive terminal and a negative terminal; a normally open bypass circuit path comprising:
a first electrical conductor connected to the negative terminal of the electrical storage cell;
a second electrical conductor connected to the positive terminal of the electrical storage cell; and
a shorting gap between the first electrical conductor and the second electrical conductor;
a mass of meltable material; a heat source activatable upon the occurrence of a voltage reversal of the electrical storage cell, the heat source being operable to melt at least a portion of the meltable material; a plunger comprising a head and a stem,
the stem extending towards the meltable material and the head having an electrically conductive face; and
a biasing mechanism positioned to push the plunger into the meltable material, when the mass of the meltable material is at least partially molten, such that the conductive face of the head of the plunger physically contacts the first electrical conductor and the second electrical conductor to close the shorting gap and bridge electrical communication between the first conductor and the second electrical conductor.

10 . The battery system of claim 9 wherein the biasing mechanism comprises a spring positioned to push the plunger into the meltable material when the meltable material is at least partially molten.

11 . The battery system of claim 9 further comprising an electrically non-conductive spacer disposed between the heat source and the meltable material.

12 . The battery system of claim 9 further comprising an electrically non-conductive carrier that at least partially encloses the meltable material, the plunger, and the biasing mechanism.

13 . The battery system of claim 9 wherein the heat source comprises a first diode and a second diode that are electrically connected in series.

14 . The battery system of claim 13 wherein:
each of the first and second diodes has a cathode and an anode;
the anode of the first diode is electrically connected to the negative terminal of the electrical storage cell and the cathode of the second diode is electrically connected to the positive terminal of the electrical storage cell;
each of the first and second diodes is heat source activatable upon the occurrence of an a voltage reversal of the electrical storage cell; and
each of the first and second diodes independently has a sufficient heat output to melt the mass of the meltable material.

15 . The battery system of claim 9 wherein the meltable material is a wax.

16 . The battery system of claim 9 wherein the meltable material is paraffin.

17 . The battery system of claim 9 wherein the meltable material has a melting point of no more than about 128 degrees F.

18 . The battery system of claim 9 further comprising a second electrical storage cell in an electrical series relationship.

Assignees

• Boeing Co

Inventors

• Becker-Irvin Craig H
• Powers Allen R

Classifications

• H01M2200/103

  Fuse · CPC title

• H01M2010/4271

  Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing · CPC title

• H01M10/425 Primary

  Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing (printed circuits H05K1/00) · CPC title

• H01M2/348

  Electricity · mapped topic

• Y02P70/50

  Manufacturing or production processes characterised by the final manufactured product · CPC title