BATTERY INTERNAL SHORT-CIRCUIT DETECTING DEVICE AND METHOD, BATTERY PACK, AND ELECTRONIC DEVICE SYSTEM

• US 20100188054A1
• Filed: 07/23/2008
• Published: 07/29/2010
• Est. Priority Date: 07/26/2007
• Status: Abandoned Application

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Fujikawa, Masato, Nakashima, Takuya, Nakatsuji, Toshiyuki, Asakura, Jun
• Application Number:
  US12/670,597
• Publication Number:
  US 20100188054A1
• Time in Patent Office: Days
• US Class Current: 320/161
• CPC Class Codes: G01R 31/36 Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
• CPC Class Codes: G01R 31/52 Testing for short-circuits, leakage current or ground faults
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 4/136 Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
• CPC Class Codes: H01M 4/5825 Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
• CPC Class Codes: H01M 50/569 Constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals battery terminal connectors with integrated measuring arrangements G01R31/364
• CPC Class Codes: H02J 7/00712 the cycle being controlled or terminated in response to electric parameters
• 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

An internal short-circuit detecting device for detecting an internal short circuit of a battery being subjected to constant current charge using a constant current amount (I) has: a voltage detection unit for detecting a terminal voltage of the battery; a terminal voltage acquisition unit for acquiring a terminal voltage (V1), as predetermined by the voltage detection unit, at a starting point of a first period (ΔW1) and a terminal voltage (V2) at an ending point; a voltage increase amount calculation unit for calculating an actual increase amount (ΔV3) of the terminal voltage of the first period (ΔW1) from the terminal voltages (V1 and V2); a voltage increase amount prediction unit for calculating a predicted increase amount (ΔV4) of the terminal voltage for the period when charging is performed using the current amount (I) for the first period (ΔW1); and an internal short-circuit determination unit for determining that the internal short circuit is generated when the actual increase amount (ΔV3) is equal to or lower than the sum of the predicted increase amount (ΔV4) and a predetermined coefficient (α).

Claims

1. An internal short-circuit detecting device for detecting an internal short circuit of a battery being subjected to constant current charge using a constant current amount I,

the internal short-circuit detecting device comprising:

a voltage detection unit for detecting a terminal voltage of the battery;

a terminal voltage acquisition unit for acquiring a terminal voltage V1, as predetermined by the voltage detection unit, at a starting point of a first period Δ

W1 and a terminal voltage V2 at an ending point;

a voltage increase amount calculation unit for calculating an actual increase amount Δ

V3 of the terminal voltage of the first period Δ

W1 from the terminal voltages V1 and V2;

a voltage increase amount prediction unit for calculating a predicted increase amount Δ

V4 of the terminal voltage for the period when charging is performed using the current amount I for the first period Δ

W1; and

an internal short-circuit determination unit for determining that an internal short circuit is generated, when the actual increase amount Δ

V3 is equal to or lower than the sum of the predicted increase amount Δ

V4 and a predetermined coefficient α

.

3. The internal short-circuit detecting device according to claim 1, wherein the battery is a nonaqueous electrolyte secondary battery that has a heat-resistant layer between a negative electrode and a positive electrode thereof, or a nonaqueous electrolyte secondary battery with an electrode plate resistance of at least 4Ω

·

cm².

7. A battery pack, comprising:

a battery; and

the internal short-circuit detecting device according to claim 1.

8. An electronic device system, comprising:

a battery;

a loading device supplied with power from the battery; and

the internal short-circuit detecting device according to claim 1.

2. An internal short-circuit detecting device for detecting an internal short circuit of a battery being subjected to constant voltage charge using a constant voltage V,

the internal-short circuit detecting device comprising:

a current detection unit for detecting a charging current of the battery;

a charging current acquisition unit for acquiring a charging current I1, as predetermined by the current detection unit, at a starting point of a second period Δ

W2 and a charging current I2 at an ending point;

a current decrease amount calculation unit for calculating an actual current decrease amount Δ

I3 of the second period Δ

W2 from the charging currents I1 and I2;

a current decrease amount prediction unit for calculating a predicted decrease amount Δ

I4 for the period when charging is performed using the voltage V for only the second period Δ

W2; and

an internal short-circuit determination unit for determining that an internal short circuit is generated, when the actual current decrease amount Δ

I3 is equal to or lower than the sum of the predicted decrease amount Δ

I4 and a predetermined coefficient β

.

4. An internal-short circuit detecting method for detecting an internal short circuit of a battery being subjected to constant current charge using a constant current amount I,

the internal short-circuit detecting method comprising:

a step of detecting a terminal voltage of the battery;

a step of acquiring a terminal voltage V1, as predetermined by the voltage detection unit, at a starting point of a first period Δ

W1 and a terminal voltage V2 at an ending point;

a step of calculating an actual increase amount Δ

V3 of the terminal voltage of the first period Δ

W1 from the terminal voltages V1 and V2;

a step of calculating an predicted increase amount Δ

V4 of the terminal voltage during the period when charging is performed using the current amount I for the first period Δ

W1; and

an internal short-circuit determination step of determining that an internal short circuit is generated, when the actual increase amount Δ

V3 is equal to or lower than the sum of the predicted increase amount Δ

V4 and a coefficient α

.

6. The internal short-circuit detecting method according to claim 4, wherein the battery is a nonaqueous electrolyte secondary battery that has a heat-resistant layer between a negative electrode and a positive electrode thereof, or a nonaqueous electrolyte secondary battery with an electrode plate resistance of at least 4Ω

·

cm².

5. A battery internal short-circuit detecting method for detecting an internal short circuit of a battery being subjected to constant voltage charge using a constant voltage V,

the internal short-circuit detecting method comprising:

a step of detecting a charging current of the battery;

a step of acquiring a charging current I1, as predetermined by the current detection unit, at a starting point of a second period Δ

W2 and a charging current I2 at an ending point;

a step of calculating an actual current decrease amount Δ

I3 of the second period Δ

W2 from the charging currents I1 and I2;

a step of calculating a predicted decrease amount Δ

I4 for the period when charging is performed using the voltage V only for the second period Δ

W2; and

an internal short-circuit determination step of determining that an internal short circuit is generated, when the actual current decrease amount Δ

I3 is equal to or lower than the sum of the predicted decrease amount Δ

I4 and a predetermined coefficient β

.