Temperature-Switched Buffer Capacitor for Battery-Powered Sensors

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing measuring devices face challenges in maintaining long-term, maintenance-free operation across varying temperatures due to battery performance fluctuations, leading to potential battery failure and reduced battery life.

Innovation Solution

Incorporating a switchable buffer capacitor that is charged by the energy storage device and selectively activated based on ambient temperature to supplement power supply to the measuring electronics, reducing the load on the energy storage device during current peaks.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If the energy storage device supplies all electrical current to the measuring electronics, then the device structure remains simple, but the battery life is reduced due to current peaks especially at low temperatures

Engineering Contradiction:
Improvedevice structureVSAvoidbattery life
Core Design Contradiction:
Device complexityVSDuration of action of moving object

Solution Approach 1:

The power supply function is segmented into two components: the energy storage device (battery) and the buffer capacitor. The buffer capacitor handles current peaks while the battery provides steady-state power, dividing the load to extend battery life without significantly increasing overall device complexity

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The buffer capacitor acts as an intermediary between the energy storage device and the measuring electronics. It absorbs current peaks and supplies additional current during high-demand periods, protecting the battery from excessive current draws especially at low temperatures

Inventive Principle:
Principle #24Intermediary (Mediator)

2Duration of action of moving object

If a buffer capacitor is added to handle current peaks, then the battery life is extended, but the device complexity increases

Engineering Contradiction:
Improvebattery lifeVSAvoiddevice structure
Core Design Contradiction:
Duration of action of moving objectVSDevice complexity

Solution Approach 1:

The power supply system is divided into battery and buffer capacitor components, each handling different aspects of the power delivery. This segmentation allows the battery to operate in its optimal range while the capacitor handles transient demands

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The buffer capacitor is switched dynamically based on temperature conditions. At low temperatures where battery performance degrades, the capacitor is activated to provide additional current. At higher temperatures, the capacitor can be disconnected to reduce complexity and power consumption

Inventive Principle:
Principle #15Dynamics

3Reliability

If the buffer capacitor is kept connected to handle current peaks, then the power supply stability is improved, but energy is wasted due to continuous charging and discharge cycles

Engineering Contradiction:
Improvepower supply stabilityVSAvoidenergy waste
Core Design Contradiction:
ReliabilityVSLoss of energy

Solution Approach 1:

The buffer capacitor is activated periodically or conditionally based on temperature thresholds rather than remaining continuously connected. This periodic activation reduces unnecessary charging/discharging cycles and associated energy losses while maintaining power supply stability when needed

Inventive Principle:
Principle #19Periodic action

Solution Approach 2:

The system uses temperature sensing and control logic to determine when the buffer capacitor should be activated. This feedback mechanism ensures the capacitor is only connected when actually needed (at low temperatures), avoiding continuous operation and associated energy waste

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

Extends the operational lifespan of the measuring device by stabilizing power supply and preventing battery drain from current peaks, ensuring continuous and error-free operation over extended periods.

Implementation Method 1

a buffer capacitor (5) which can be charged by means of the energy storage device (4) and which, in addition to the energy storage device (4), can supply an electrical current to the measuring electronics (3)

Methodology Applied
Scientific EffectCapacitance: Capacitance

Data Source

PatentEP4257931B1Measuring device and associated operating method
Publication Date: 2025.10.15 TESTO SE & CO KGAA
  • EP4257931B1 patent drawingFigure 1

AI summary

To extend the maintenance-free and self-sufficient operation of an electrical measuring device (1), which has an internal energy storage device (4) and measuring electronics (3) for reading a sensor (2), the latter being designed to detect an environmental parameter such as room temperature or humidity, it is proposed that, as required, depending on an ambient temperature detected by the measuring device (1), a buffer capacitor (5) is electrically connected to the energy storage device (4) in such a way that the buffer capacitor (5) can draw electrical power from the energy storage device (4) and make this power available again, in particular when the electrical operating voltage of the measuring device (1) drops, in order to buffer current peaks of a load current of the measuring electronics (3).