Battery Pack Resistive Identification for Power Tool Compatibility
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Smaller, lower voltage power tool battery packs lack intelligence, making it difficult for devices to determine the features or configuration of these battery packs.
Innovation Solution
The battery pack systems include a resistive element connected to a battery cell and an external device with a controller that measures voltage across the resistive elements to determine the battery pack's identity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If smaller, lower voltage battery packs are used, then the battery pack size and voltage are reduced, but the intelligence and ability to communicate battery parameters is lost
Solution Approach 1:
The battery pack identification system is segmented into distinct functional components: identification circuits within the battery pack, sensing circuits in the external device, and a controller that processes the signals. This segmentation allows the intelligence to be distributed rather than centralized, enabling smaller battery packs to communicate their parameters through dedicated identification circuits while maintaining the ability to convey battery configuration information.
2Measurement precision
If identification circuits are added to battery packs, then battery pack identification capability is improved, but the device complexity increases
Solution Approach 1:
The patent extracts the intelligence and identification capability from the battery pack itself and places it in the external device (power tool or charger). The battery pack only needs to provide passive identification elements (resistive elements with specific resistance values), while the active sensing, signal processing, and decision-making circuits are located in the external device. This extraction reduces the complexity burden on the battery pack while maintaining accurate identification capability.
Solution Approach 2:
The identification circuits in the battery pack use simple, inexpensive passive components (resistors with specific resistance values) rather than complex active electronics. These passive resistive elements serve as the identification medium, replacing what would otherwise require sophisticated communication circuits. The simplicity of using basic resistive elements rather than complex communication modules reduces both cost and complexity while achieving the identification function.
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 solution allows devices to accurately identify the battery pack's parameters and features, enabling optimized performance and charging strategies.
Implementation Method 1
a first resistive element connected to a positive electrode of a first battery cell
Implementation Method 2
measure a voltage between the first resistive element and the second resistive element
Implementation Method 3
a thermistor, and a capacitor connected in parallel with the thermistor
Data Source
AI summary
Systems described herein include a battery pack including one or more battery cells and a first resistive element connected to a positive electrode of a first battery cell. The systems also include an external device capable of receiving the battery pack. The external device includes a second resistive element, a switch, and a controller. The second resistive element is configured to be in series with the first resistive element upon the battery pack being received within the external device. The switch is positioned in series with the second resistive element and a common potential is coupled to both the battery pack and the external device. The controller is configured to activate the switch, measure a voltage between the first resistive element and the second resistive element in response to the switch being activated, and determine an identification of the battery pack based on the measured voltage.