Materials

This section provides an overview of materials, components, and devices used in electrochemical systems.

Active Material

IRI: https://w3id.org/emmo/domain/electrochemistry#electrochemistry_79d1b273_58cd_4be6_a250_434817f7c261

Description The active material, also known as the electrochemically active material, is a key component of an electrochemical system that undergoes an electrochemical reaction (oxidation or reduction) at an electrode. These reactions are responsible for enabling energy storage and release in devices such as batteries.

For example, during the discharging of an electrochemical cell: - The active material on the anode is oxidized, releasing electrons. - The active material on the cathode is reduced, consuming electrons.

The active material determines the cell’s capacity, voltage, and energy density, making it one of the most critical aspects of any electrochemical device.

Examples of Active Materials Here are some commonly used active materials in electrochemical systems:

Common Active Materials

Name	Label	IRI
Zinc	Zinc	IRI: https://w3id.org/emmo/domain/chemical-substance#substance_9bd78e1c_a4dc_41b6_8013_adb51df1ffdc
Manganese Dioxide	ManganeseDioxide	IRI: https://w3id.org/emmo/domain/chemical-substance#substance_dcdbdbed_2e20_40d1_a7a5_5761de7f0618
Graphite	Graphite	IRI: https://w3id.org/emmo/domain/chemical-substance#substance_d53259a7_0d9c_48b9_a6c1_4418169df303
Lithium Iron Phosphate	LithiumIronPhosphate	IRI: https://w3id.org/emmo/domain/chemical-substance#substance_aa8e9cc4_5f66_4307_b1c8_26fac7653a90

Usage To describe an active material in the ontology, start by defining its properties. The active material can then be linked to an Electrode or ElectrodeCoating object using the property hasActiveMaterial. This property establishes the relationship between the electrode or its coating and the active material responsible for the electrochemical reaction.

Steps to Describe an Active Material with the Ontology:

1. Define the Active Material: Specify the properties of the active material itself, such as its chemical composition, physical state, and relevant characteristics. Use ontology properties to describe these attributes. Common annotation properties for an active material include: - molecularFormula: Defines the chemical formula or composition of the material.

   Common objective properties for an active material include: - Density: Specifies the density of the material. - SpecificCapacity: Describes the amount of electric charge per unit mass the material can store.

   Example Here’s an example of how to describe the properties of Lithium Iron Phosphate:

2. Link the Active Material to an Electrode or Coating: Once the active material is defined, associate it with an Electrode or ElectrodeCoating object. Use the hasActiveMaterial property to establish this relationship.

   Example Here’s an example of how to link an active material to an electrode or coating:

   • To link Zinc to an electrode: .. code-block:: json

     {

     “@context”: “https://w3id.org/emmo/domain/electrochemistry/context”, “@type”: “Electrode”, “hasActiveMaterial”: {

     “@type”: “Zinc”

     }

     }

   • To link Graphite to an electrode coating: .. code-block:: json

     {

     “@context”: “https://w3id.org/emmo/domain/electrochemistry/context”, “@type”: “CoatedElectrode”, “hasCoating”: {

     “@type”: “ElectrodeCoating”, “hasActiveMaterial”: {

     “@type”: “Graphite”

     }

     }

     }

Tip

Predefined Electrode Classes with Linked Active Materials

For very common active material types, especially those covered by IEC designations, the ontology provides specific electrode classes where the type of active material is already linked. These predefined classes can save time if you just want to convey the type of active material used in a general way.

For example, the ZincElectrode class in the ontology already links the active material Zinc to the electrode.

To represent a generic zinc electrode: .. code-block:: json

{

“@context”: “https://w3id.org/emmo/domain/electrochemistry/context”, “@type”: “ZincElectrode”

}

For cases where you want to say that your electrode uses a specific kind of zinc material, then you can still use the hasActiveMaterial property in the same way: .. code-block:: json

{

“@context”: “https://w3id.org/emmo/domain/electrochemistry/context”, “@type”: “ZincElectrode”, “hasActiveMaterial”: {

“@type”: “Zinc”, “@id”: “https://www.example.com/Your_Specific_Zinc_Material_Identifier”

}

Additional Examples and Resources - Templates: - JSON-LD examples: - Jupyter notebooks:

Electrolyte

Binder

Other Materials