Battery Current Interrupt Unit with Parallel Voltage Drop Protection

Solution Overview

Problem

The existing battery units fail to prevent overdischarge or overcharge when the switching means is in failure, and using a voltage drop element with a large maximum allowable current increases production costs and space requirements.

Innovation Solution

A battery apparatus with a current interrupt unit, a parallel circuit including a voltage drop element, and a control unit that switches the current interrupt unit to an interruption state when a high load exceeding the maximum allowable current is not activated, preventing excessive current from flowing through the voltage drop element.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a voltage drop element with larger maximum allowable current is used, then the reliability of failure diagnosis is improved, but the area of mounting space and production cost are increased

Engineering Contradiction:

Improvefailure diagnosis reliabilityVSAvoidmounting space

Core Design Contradiction:

ReliabilityVSArea of stationary object

Solution Approach 1:

The control unit switches the current interrupt unit to an interruption state before activating the high load, preventing excessive current from flowing through the voltage drop element during diagnosis. This preliminary action allows the use of a smaller voltage drop element while maintaining diagnostic reliability.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system dynamically controls the state of the current interrupt unit based on the activation status of high loads. When a high load is not activated, the current interrupt unit is switched to interruption state to protect the voltage drop element, allowing the use of a smaller element with lower current rating.

Inventive Principle:

Principle #15Dynamics

2Reliability

If a voltage drop element with larger maximum allowable current is used, then the reliability of failure diagnosis is improved, but the production cost is increased

Engineering Contradiction:

Improvefailure diagnosis reliabilityVSAvoidproduction cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The control unit switches the current interrupt unit to an interruption state before activating the high load, preventing excessive current from flowing through the voltage drop element during diagnosis. This preliminary action allows the use of a smaller voltage drop element while maintaining diagnostic reliability.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system dynamically controls the state of the current interrupt unit based on the activation status of high loads. When a high load is not activated, the current interrupt unit is switched to interruption state to protect the voltage drop element, allowing the use of a smaller element with lower current rating.

Inventive Principle:

Principle #15Dynamics

3Reliability

If the switching means is in failure, then the battery unit cannot prevent overdischarge or overcharge, but adding protection increases system complexity

Engineering Contradiction:

Improvebattery protection reliabilityVSAvoidsystem complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The voltage drop element is connected in parallel with the current interrupt unit, combining the protection function with the existing switching mechanism. This integrated approach provides battery protection without significantly increasing system complexity.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The control unit monitors the state of the current interrupt unit and the activation status of high loads, providing feedback control to switch the current interrupt unit to the appropriate state. This feedback mechanism ensures reliable battery protection while maintaining manageable system complexity.

Inventive Principle:

Principle #23Feedback

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This configuration prevents the voltage drop element from being broken due to large currents without using a high-capacity voltage drop element, allowing for efficient failure diagnosis and preventing battery overcharge or overdischarge states, while reducing production costs and space requirements.

Implementation Method 1

a parallel circuit connected in parallel with the current interrupt unit and including a voltage drop element that causes a voltage drop when current flows therethrough

Methodology Applied

Scientific EffectVoltage drop: Electrical Resistance

Data Source

PatentUS10305299B2Battery apparatus, vehicle, battery management program, and management method of battery apparatus

Publication Date: 2019.05.28 GS YUASA INT LTD

AI summary

A battery apparatus disclosed in the present specification includes: an energy storage device that supplies power to a vehicle load mounted on a vehicle; a current interrupt unit that causes the energy storage device and the vehicle load to be in a conduction state or in an interruption state; a parallel circuit connected in parallel with the current interrupt device and including a diode that causes a voltage drop when current flows therethrough; and a control unit, wherein a CPU in the control unit executes an interruption process for switching the current interrupt device to an interruption state to detect a voltage between both ends of the current interrupt device, when a high load that is to be activated by supply of power exceeding maximum allowable current of the diode is not activated.