pymatgen.apps.battery.conversion_battery module

class ConversionElectrode(voltage_pairs, working_ion_entry, initial_comp)

Bases: pymatgen.apps.battery.battery_abc.AbstractElectrode

Class representing a ConversionElectrode.

General constructor for ConversionElectrode. However, it is usually easier to construct a ConversionElectrode using one of the static constructors provided.

Parameters:

• voltage_pairs – The voltage pairs making up the Conversion Electrode.
• working_ion_entry – A single ComputedEntry or PDEntry representing the element that carries charge across the battery, e.g. Li.
• initial_comp – Starting composition for ConversionElectrode.

as_dict()

composition

static from_composition_and_entries(comp, entries_in_chemsys, working_ion_symbol='Li')

Convenience constructor to make a ConversionElectrode from a composition and all entries in a chemical system.

Parameters:

• comp – Starting composition for ConversionElectrode, e.g., Composition(“FeF3”)
• entries_in_chemsys – Sequence containing all entries in a chemical system. E.g., all Li-Fe-F containing entries.
• working_ion_symbol – Element symbol of working ion. Defaults to Li.

static from_composition_and_pd(comp, pd, working_ion_symbol='Li')

Convenience constructor to make a ConversionElectrode from a composition and a phase diagram.

Parameters:

• comp – Starting composition for ConversionElectrode, e.g., Composition(“FeF3”)
• pd – A PhaseDiagram of the relevant system (e.g., Li-Fe-F)
• working_ion_symbol – Element symbol of working ion. Defaults to Li.

classmethod from_dict(d)

get_sub_electrodes(adjacent_only=True)

If this electrode contains multiple voltage steps, then it is possible to use only a subset of the voltage steps to define other electrodes. For example, an LiTiO2 electrode might contain three subelectrodes: [LiTiO2 –> TiO2, LiTiO2 –> Li0.5TiO2, Li0.5TiO2 –> TiO2] This method can be used to return all the subelectrodes with some options

Parameters:adjacent_only – Only return electrodes from compounds that are adjacent on the convex hull, i.e. no electrodes returned will have multiple voltage steps if this is set true Returns:A list of ConversionElectrode objects

get_summary_dict(print_subelectrodes=True)

Parameters:print_subelectrodes – Also print data on all the possible subelectrodes Returns:a summary of this electrode”s properties in dictionary format

is_super_electrode(conversion_electrode)

Checks if a particular conversion electrode is a sub electrode of the current electrode. Starting from a more lithiated state may result in a subelectrode that is essentially on the same path. For example, a ConversionElectrode formed by starting from an FePO4 composition would be a super_electrode of a ConversionElectrode formed from an LiFePO4 composition.

voltage_pairs

working_ion

The working ion as an Element object

working_ion_entry

class ConversionVoltagePair(balanced_rxn, voltage, mAh, vol_charge, vol_discharge, mass_charge, mass_discharge, frac_charge, frac_discharge, entries_charge, entries_discharge, working_ion_entry)

Bases: pymatgen.apps.battery.battery_abc.AbstractVoltagePair

A VoltagePair representing a Conversion Reaction with a defined voltage. Typically not initialized directly but rather used by ConversionElectrode.

Parameters:

• balanced_rxn (BalancedReaction) – BalancedReaction for the step
• voltage (float) – Voltage for the step
• mAh (float) – Capacity of the step
• vol_charge (float) – Volume of charged state
• vol_discharge (float) – Volume of discharged state
• mass_charge (float) – Mass of charged state
• mass_discharge (float) – Mass of discharged state
• frac_charge (float) – Fraction of working ion in the charged state
• frac_discharge (float) – Fraction of working ion in the discharged state
• entries_charge ([ComputedEntry]) – Entries in the charged state
• entries_discharge ([ComputedEntry]) – Entries in discharged state
• working_ion_entry (ComputedEntry) – Entry of the working ion.

as_dict()

entries_charge

entries_discharge

frac_charge

frac_discharge

classmethod from_dict(d)

static from_steps(step1, step2, normalization_els)

Creates a ConversionVoltagePair from two steps in the element profile from a PD analysis.

Parameters:

• step1 – Starting step
• step2 – Ending step
• normalization_els – Elements to normalize the reaction by. To ensure correct capacities.

mAh

mass_charge

mass_discharge

rxn

vol_charge

vol_discharge

voltage

working_ion

working_ion_entry