Autonomous Power Supply with Capacitor De-passivation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium thionyl chloride batteries in autonomous systems suffer from passivation, which increases internal resistance and renders them unusable over time, especially when under low demand, due to the formation of a passive electrode layer.
Innovation Solution
A power supply device with an electrical capacitor connected in parallel to the battery, controlled by a microcontroller to selectively manage switch states, allowing for de-passivation and optimized energy distribution by switching between batteries and capacitors based on current demand, thereby minimizing passivation and internal resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If lithium thionyl chloride batteries are used in autonomous systems with low demand, then high energy density and limited self-discharge are achieved, but passivation occurs increasing internal resistance and rendering them unusable
Solution Approach 1:
The system performs preliminary action by periodically activating batteries through switching operations before complete passivation occurs. The microcontroller monitors battery states and initiates switching sequences to maintain electrode activity, preventing the formation of stable passive layers that would increase internal resistance and render batteries unusable.
Solution Approach 2:
The invention implements periodic action through cyclic switching operations between parallel battery connections. The microcontroller executes periodic sequences that alternately connect and disconnect batteries, creating regular current pulses that prevent passivation without requiring continuous high current draw. This periodic activation maintains battery usability while preserving the high energy density characteristics.
2Reliability
If current is drawn from battery to de-passivate it, then passivation is reduced, but energy consumption increases
Solution Approach 1:
The system merges multiple batteries in parallel configuration, allowing the current draw for de-passivation to be distributed across multiple battery units. When one battery requires de-passivation, other batteries can supply the necessary current while simultaneously being charged, thereby reducing the net energy loss from the overall system rather than drawing from a single battery's stored energy.
Solution Approach 2:
The battery system performs self-service through internal energy redistribution. During switching operations, batteries that are less passivated or have higher charge states automatically supply current to de-passivate other batteries in the array. This self-service mechanism reduces the need for external energy input while maintaining all batteries in an usable state.
3Power
If multiple batteries are connected in parallel, then current supply capability is increased, but passivation occurs more rapidly in each individual battery
Solution Approach 1:
The system applies dynamics by implementing active switching control between parallel battery connections. Instead of leaving batteries permanently connected in parallel, the microcontroller dynamically switches connections based on real-time battery states, current demands, and passivation levels. This dynamic management allows the system to maintain high current supply capability while periodically isolating individual batteries to prevent rapid passivation.
Solution Approach 2:
The invention implements discarding and recovering by temporarily disconnecting (discarding) individual batteries from the parallel configuration when they show signs of passivation. During this isolation period, the battery is recovered through controlled charging or de-passivation operations. This cycle of discarding problematic batteries and recovering them prevents the cumulative passivation effect that would occur with continuous parallel connection.
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
The solution effectively prevents passivation, optimizes energy supply, and reduces internal resistance by selectively using batteries and capacitors, ensuring reliable long-term operation of autonomous systems.
Implementation Method 1
an electrical capacitor mounted in parallel with the battery or batteries
Implementation Method 2
the capacitor being connected to an output terminal via at least one respective switch
Implementation Method 3
each elementary battery and the capacitor being connected to an output terminal via a respective first switch
Data Source
Figure 1~2
AI summary
Method and device for powering a self-contained electrical device comprising at least one elementary battery (1, 2), in particular of the lithium type, the battery or batteries (1, 2) being connected between two output terminals (4, 5), characterized in that it comprises an electrical capacitor (3) mounted in parallel with the battery or batteries (1, 2), each elementary battery (1, 2) and the capacitor (3) being connected to an output terminal (4) via at least one respective switch (11, 12, 13), the device further comprising electronic logic (6) such as a microcontroller connected to said switches (11, 12, 13) for selectively and independently controlling the open (non-conducting) or closed (conducting) state of said switches (11, 12, 13).