Case-Neutral Battery for Implantable Stimulation Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional implantable electrical stimulation systems face challenges in terms of size and shape limitations, which restrict implantation locations and can cause cosmetic issues due to tissue bulging, and inductive charging generates heat that may exceed the tolerance of surrounding tissues, limiting recharge rates.
Innovation Solution
A control module with a case-neutral battery design, where the battery case is electrically isolated from the electrodes, allowing for reduced size and safer inductive charging by positioning the battery within a recess in the skull, which can tolerate higher temperatures than subcutaneous tissue, enabling faster charging without overheating.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the control module is implanted in subcutaneous tissue, then it is easier to implant, but the tissue bulges cosmetically and has low temperature tolerance
Solution Approach 1:
The invention transitions from subcutaneous implantation to intracranial implantation, moving the control module into a different anatomical dimension (inside the skull). This resolves the cosmetic bulging issue by utilizing the intracranial space that does not cause external tissue deformation, while still allowing access to neural structures through the skull base or foramen magnum.
Solution Approach 2:
The skull acts as an intermediary structure between the control module and the external environment. By implanting within the cranial cavity, the skull provides structural support and eliminates the cosmetic visibility issue, while the control module can still function through wireless communication and leadless electrode connections.
2Ease of operation
If the control module is implanted in subcutaneous tissue, then it is easier to implant, but the temperature tolerance is too low for safe inductive charging
Solution Approach 1:
The invention moves the control module from subcutaneous tissue to intracranial placement, utilizing the different thermal properties of bone tissue. The skull provides superior heat dissipation capabilities compared to soft tissue, enabling safer inductive charging with higher power densities without causing thermal damage to surrounding structures.
Solution Approach 2:
The invention changes the thermal environment parameter by selecting a bone-based implantation site instead of soft tissue. Bone tissue has higher thermal conductivity and tolerance, allowing the system to operate at higher charging temperatures that would be unsafe in subcutaneous locations, thereby enabling faster and safer battery recharging.
3Device complexity
If a conventional battery design is used, then the structure is simpler, but the size and shape limit implantation locations
Solution Approach 1:
The invention segments the control module into modular components: a hermetically sealed electronics housing containing the control circuitry, and a separate rechargeable battery assembly. This segmentation allows independent optimization of each component's shape and size, enabling adaptation to the intracranial space constraints while maintaining structural simplicity through standardized connection interfaces.
Solution Approach 2:
By adopting a case-neutral battery design where the battery case is electrically isolated from the electrodes, the invention eliminates the need for additional insulating layers and protective housings. This reduces the overall envelope size and allows flexible orientation and placement within the three-dimensional intracranial space, significantly increasing implantation location options.
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 design increases the number of implantable locations, improves cosmetic outcomes by reducing tissue bulging, and allows for safer and faster battery recharging by leveraging the higher temperature tolerance of bone tissue.
Implementation Method 1
the battery case forms a hermetic seal around the positive electrode and the negative electrode
Implementation Method 2
The battery case is electrically isolated from each of the positive electrode and the battery electrode
Implementation Method 3
inductive charging generates heat that may exceed the tolerance of surrounding tissues
Implementation Method 4
the battery case is attached to the electronics housing via at least one of a weld or adhesive
Data Source
AI summary
A control module for an electrical stimulation system includes a sealed electronics housing; an electronic subassembly disposed within the electronics housing; one or more connector assemblies coupled to the electronic subassembly; and a rechargeable battery disposed external to the electronics housing. The one or more connector assemblies are configured to receive a lead. The rechargeable battery includes a positive electrode, a negative electrode, and a single battery case attached directly to the sealed electronics housing and forming a sealed cavity that encapsulates both the positive electrode and the negative electrode. The battery case is electrically isolated from each of the positive electrode and the battery electrode.