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.

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

Guidelines for Use#

To represent an Active Material in the ontology, follow three key steps:

Identify the Material Determine what the material is by combining terms from the domain-chemical-substance ontology with the ActiveMaterial class in the electrochemistry domain.
Assign Properties Define the material’s attributes using annotation properties (e.g., molecularFormula) and quantitative properties (e.g., Density, SpecificCapacity).
Link the Material to a Functional Whole Use object properties like hasActiveMaterial to connect the material to an Electrode or ElectrodeCoating.

Step 1: Identifying the Active Material#

Begin by defining the chemical identity of the material. This includes assigning it a class and a name that aligns with established chemical substance ontologies.

Example: Defining Zinc as an active material:

{
  "@context": "https://w3id.org/emmo/domain/electrochemistry/context",
  "@type": ["ActiveMaterial", "Zinc"]
}

Step 2: Assigning Properties#

Once the material is identified, define its intrinsic properties using annotation and quantitative properties.

Annotation Properties: - molecularFormula: Defines the chemical composition.
Objective Properties: - Density: Specifies the material’s density. - SpecificCapacity: Describes the charge storage capacity per unit mass.

Example: Adding properties to Zinc:

{
  "@context": "https://w3id.org/emmo/domain/electrochemistry/context",
  "@type": ["ActiveMaterial", "Zinc"],
  "molecularFormula": "Zn",
  "hasProperty": [
    {
      "@type": "Density",
      "hasNumericalPart": {
        "@type": "RealData",
        "hasNumberValue": 7.14
      },
      "hasMeasurementUnit": "emmo:GramPerCubicCentiMetre"
    },
    {
      "@type": "SpecificCapacity",
      "hasNumericalPart": {
        "@type": "RealData",
        "hasNumberValue": 820
      },
      "hasMeasurementUnit": "emmo:MilliAmpereHourPerGram"
    }
  ]
}

Step 3: Linking the Active Material to a Functional Whole#

The final step is to associate the active material with a functional component, such as an Electrode or ElectrodeCoating, using the hasActiveMaterial property.

Example: Linking Zinc to an Electrode:

{
  "@context": "https://w3id.org/emmo/domain/electrochemistry/context",
  "@type": "Electrode",
  "hasActiveMaterial": {
    "@type": "Zinc"
  }
}

Example: Linking Zinc to an Electrode Coating:

{
  "@context": "https://w3id.org/emmo/domain/electrochemistry/context",
  "@type": "CoatedElectrode",
  "hasCoating": {
     "@type": "ElectrodeCoating",
     "hasActiveMaterial": {
         "@type": "Zinc"
     }
  }
}

By following these three steps — identifying the material, assigning properties, and linking it to a functional structure — active materials are consistently defined within the ontology, ensuring semantic clarity and interoperability.

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:

   {
     "@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:

{
  "@context": "https://w3id.org/emmo/domain/electrochemistry/context",
  "@type": "ZincElectrode",
  "hasActiveMaterial": {
      "@type": "Zinc",
      "@id": "https://www.example.com/Your_Specific_Zinc_Material_Identifier"
}