Adjustable Current Limit Regulator for Battery Charging

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Solution Overview

Problem

Existing battery charging systems are inflexible and inefficient, often damaging batteries due to improper voltage and current handling, leading to long charging times and potential explosions, and fail to optimize battery cell capacity.

Innovation Solution

A battery charging system with an adjustable current limit regulator that monitors input voltage and adjusts current to prevent exceeding the power source's maximum capacity, using either switching or linear regulators to ensure safe and efficient charging.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If static battery charging systems with hardwired circuits are used, then the system structure is simple, but the adaptability to different power sources and battery specifications is poor

Engineering Contradiction:
Improveadaptability to different power sourcesVSAvoidsystem complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent implements dynamic adaptability by enabling the battery charging system to automatically detect power source characteristics (AC or DC) and battery specifications, then dynamically adjust charging parameters including current limits, voltage levels, and charging algorithms. The controller modifies operating parameters in real-time based on detected conditions, transforming a static system into a dynamic one that adapts to varying power sources and battery types without requiring complex manual configuration or multiple dedicated circuits.

Inventive Principle:
Principle #15Dynamics

2Productivity

If high current is supplied to charge the battery quickly, then the charging speed increases, but the battery may be damaged or explode

Engineering Contradiction:
Improvecharging speedVSAvoidbattery safety
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent implements comprehensive feedback mechanisms that continuously monitor battery voltage, current, temperature, and charge state during the charging process. The controller receives real-time feedback from sensors and automatically adjusts charging parameters to maintain safe operating conditions. The system dynamically modifies current limits based on battery state, preventing overcurrent conditions that could cause damage or explosion while still achieving fast charging when safe. This closed-loop control ensures both high charging speed and battery safety.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent dynamically changes charging parameters including current limits, voltage levels, and charging algorithms based on real-time battery state and power source characteristics. The system adjusts these parameters throughout the charging process to optimize both speed and safety, transitioning between different charging phases and modes as needed. This parameter adaptation allows the system to achieve fast charging when conditions permit while preventing dangerous conditions.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If low current is supplied to ensure battery safety, then the battery is protected from damage, but the charging time becomes very long

Engineering Contradiction:
Improvebattery safetyVSAvoidcharging time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent implements dynamic current adjustment that starts with lower current for safety during initial charging phases, then progressively increases current as the battery state improves and conditions permit. The system dynamically adapts current levels throughout the charging process rather than maintaining a fixed low current, thereby reducing total charging time while maintaining safety. The controller continuously evaluates battery state and power source capability to optimize current levels in real-time.

Inventive Principle:
Principle #15Dynamics

4Adaptability or versatility

If fixed current limit circuits are used, then the manufacturing process is simple, but the system cannot optimize battery cell capacity for different battery technologies

Engineering Contradiction:
Improveoptimization for different battery technologiesVSAvoidcurrent limit circuit complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent implements a universal charging system that can accommodate multiple battery technologies (lithium-ion, nickel-metal hydride, lead-acid, etc.) through software-based control rather than requiring different hardware circuits for each battery type. The controller contains multiple charging algorithms and parameter sets that can be selected and applied based on the detected battery type. This multi-functionality is achieved through programmable logic and stored charging profiles, eliminating the need for complex dedicated hardware circuits for each battery technology while enabling optimization for different battery types.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentEP2137802B1Battery charging systems and methods with adjustable current limit
Publication Date: 2014.12.31 QUALCOMM INC
  • EP2137802B1 patent drawingFigure 1
  • EP2137802B1 patent drawingFigure 2
  • EP2137802B1 patent drawingFigure 3

AI summary

Embodiments of the present invention include techniques for charging a battery using a regulator. In one embodiment, the present invention includes an electronic circuit comprising a regulator having an input coupled to a power source for receiving a voltage and a current and an output for providing an output current, an input voltage detection circuit coupled to the power source, and an adjustable current limit circuit for controlling the input or output current of the regulator, wherein input voltage detection circuit monitors the voltage from the power source and the adjustable current limit circuit changes the input or output current of the regulator to optimize the power drawn from power source.