This page is a detailed reference for built-in templates. See Protocols for the full guide on creating, managing, and using protocols.

Experiment Templates

Ionworks provides 9 built-in experiment templates — pre-configured battery testing protocols that can be customized with different parameters. Each template defines a protocol using the Universal Cycler Protocol (UCP) format with adjustable variables to suit your needs.

Template metrics

Some experiment templates include built-in metrics — summary values automatically computed from simulation results. When you run a simulation using one of these templates, the metrics are calculated and displayed in the Data View alongside the simulation inputs. Metrics use a declarative configuration format with these types:

Category	Types	Description
Aggregation	`First`, `Last`, `Mean`, `Minimum`, `Maximum`, `Sum`	Compute a single value from a time series variable
Crossing	`SOC`, `Voltage`, `Time`	Find the value of a variable at a specific state of charge, voltage, or time
Composed	`ComposedMetric`	Combine metrics with arithmetic operations (`add`, `sub`, `mul`, `div`, `abs`)

Metrics can also target a specific protocol step using the step field (0-indexed), which is useful for multi-step experiments like pulse resistance tests.

The same metric type system is used in Optimization Templates for defining optimization objectives and constraints.

Available Templates

1. Constant Current Discharge

Description: Discharges the battery at a constant C-rate until a voltage cutoff is reached. Adjustable Parameters:

Temperature [°C] - Operating temperature (default: 25°C)
Initial SOC [%] - Starting state of charge (default: 100%)
C-rate - Discharge rate relative to nominal capacity (default: 1C)
Cut-off voltage [V] - Minimum voltage to stop discharge (default: V_MIN)

UCP Protocol

global:
    initial_temperature: input["Temperature [°C]"]
    initial_state_type: soc_percentage
    initial_state_value: input["Initial SOC [%]"]

steps:
    - Discharge:
        mode: C-rate
        value: input["C-rate"]
        resolution:
            time: 10 / input["C-rate"]
        ends:
            - Voltage < input["Cut-off voltage [V]"]

Computed metrics:

Metric	Description
Capacity [A.h]	Final discharge capacity
Energy [W.h]	Final discharge energy
Mean internal resistance [mΩ]	Average internal resistance over the discharge
Mean current [A]	Absolute average current
Mean power [W]	Absolute average power
Min/Max anode potential [V]	Anode potential range during discharge
Min/Max cathode potential [V]	Cathode potential range during discharge

2. Constant Current Charge

Description: Charges the battery using a constant current (CC) phase followed by a constant voltage (CV) hold. This is the standard CC-CV charging protocol. Adjustable Parameters:

Temperature [°C] - Operating temperature (default: 25°C)
Initial SOC [%] - Starting state of charge (default: 0%)
C-rate - Charge rate during CC phase (default: 1C)
Cut-off voltage [V] - Maximum voltage for CC/CV phases (default: V_MAX)
CV cut-off C-rate - C-rate threshold to end CV phase (default: 0.02C)

UCP Protocol

global:
    initial_temperature: input["Temperature [°C]"]
    initial_state_type: soc_percentage
    initial_state_value: input["Initial SOC [%]"]

steps:
    - Charge:
        mode: C-rate
        value: input["C-rate"]
        resolution:
            time: 10 / input["C-rate"]
        ends:
            - Voltage > input["Cut-off voltage [V]"]
    - Charge:
        mode: Voltage
        value: input["Cut-off voltage [V]"]
        ends:
            - C-rate < input["CV cut-off C-rate"]

Computed metrics:

Metric	Description
Charge capacity [A.h]	Final charge capacity
Energy [W.h]	Final charge energy
Mean internal resistance [mΩ]	Average internal resistance
Mean current [A]	Average charging current
Mean power [W]	Absolute average power
Min/Max anode potential [V]	Anode potential range during charge
Min/Max cathode potential [V]	Cathode potential range during charge
Charge time (10-80% SOC) [min]	Time to charge from 10% to 80% state of charge, in minutes

3. GITT (Galvanostatic Intermittent Titration Technique)

Description: Alternates between current pulses and rest periods to measure quasi-equilibrium voltage as a function of state of charge. This technique separates kinetic and thermodynamic contributions to the cell voltage. This experiment will run until the voltage reaches the upper or lower voltage cut-off during the pulse phase. Adjustable Parameters:

Temperature [°C] - Operating temperature (default: 25°C)
Direction - ‘Charge’ or ‘Discharge’ (default: ‘Discharge’)
Pulse C-rate - Current rate during active pulses (default: 0.1C)
Pulse duration [s] - Length of each current pulse (default: 1800s / 30 min)
Rest duration [s] - Length of each rest period (default: 1800s / 30 min)

UCP Protocol

global:
    initial_temperature: input["Temperature [°C]"]
    initial_state_type: soc_percentage
    initial_state_value: ifelse(input["Direction"] == "Charge", 0, 100)

steps:
    - Control:
        set_variable:
            - name: VAR_IS_CHARGE
              eval: ifelse(input["Direction"] == "Charge", 1, 0)
            - name: VAR_VMAX
              eval: input["Upper voltage cut-off [V]"]
            - name: VAR_VMIN
              eval: input["Lower voltage cut-off [V]"]
    - Pulse Block:
        steps:
            - Direction[input["Direction"]]:
                mode: C-rate
                value: input["Pulse C-rate"]
                duration: input["Pulse duration [s]"]
                ends:
                    - "Voltage > ifelse(VAR_IS_CHARGE == 1, VAR_VMAX, 1e9)":
                        goto: Final Rest Block
                    - "Voltage < ifelse(VAR_IS_CHARGE == 0, VAR_VMIN, -1e9)":
                        goto: Final Rest Block
            - Rest:
                duration: input["Rest duration [s]"]
        repeat: 1000
    - Final Rest Block:
        - Rest:
            duration: input["Rest duration [s]"]

4. PITT (Potentiostatic Intermittent Titration Technique)

Description: Steps the voltage in small increments with rest periods between steps. Measures current response to voltage changes to study electrode kinetics. Adjustable Parameters:

Temperature [°C] - Operating temperature (default: 25°C)
Starting voltage [V] - Initial cell voltage (default: V_MIN)
Final voltage [V] - Target cell voltage (default: V_MAX)
Voltage step [V] - Size of voltage increments (default: 0.1V)
Pulse duration [s] - Hold time at each voltage (default: 900s / 15 min)
Rest duration [s] - Rest time between voltage steps (default: 900s / 15 min)

UCP Protocol

global:
    initial_temperature: input["Temperature [°C]"]
    initial_state_type: voltage
    initial_state_value: input["Starting voltage [V]"]

steps:
    - Control:
        set_variable:
            - name: VAR_VOLTAGE
              eval: input["Starting voltage [V]"]
            - name: VAR_CHARGE
              eval: input["Final voltage [V]"] > input["Starting voltage [V]"]
            - name: VAR_END_CONDITION
              eval: input["Final voltage [V]"]

    - Pulse Block:
        steps:
            - Direction[ifelse(VAR_CHARGE == 1, "Charge", "Discharge")]:
                mode: Voltage
                value: VAR_VOLTAGE
                duration: input["Pulse duration [s]"]
                ends:
                    - "Voltage > ifelse(VAR_CHARGE == 1, VAR_END_CONDITION, 1e9)":
                        goto: Final Rest Block
                    - "Voltage < ifelse(VAR_CHARGE == 0, VAR_END_CONDITION, -1e9)":
                        goto: Final Rest Block

            - Rest:
                set_variable:
                    - name: VAR_VOLTAGE
                      eval: VAR_VOLTAGE + input["Voltage step [V]"]
                duration: input["Rest duration [s]"]
        repeat: 1000

    - Final Rest Block:
        - Rest:
            duration: input["Rest duration [s]"]

5. Pulse Resistance

Description: Measures DC internal resistance (DCIR) using a rest-pulse-rest sequence. Quantifies the instantaneous voltage response to a current pulse. Adjustable Parameters:

Temperature [°C] - Operating temperature (default: 25°C)
Initial SOC [%] - State of charge for test (default: 50%)
C-rate - Magnitude of current pulse (default: 1C)
Direction - ‘Charge’ or ‘Discharge’ (default: ‘Discharge’)
Duration [s] - Total pulse duration (default: 10s)

UCP Protocol

global:
    initial_temperature: input["Temperature [°C]"]
    initial_state_type: soc_percentage
    initial_state_value: input["Initial SOC [%]"]

steps:
    - Rest:
        duration: input["Duration [s]"]/2
    - Discharge:
        mode: C-rate
        value: input["C-rate"]
        duration: input["Duration [s]"]
    - Rest:
        duration: input["Duration [s]"]/2

Computed metrics:

Metric	Description
Pulse overpotential [mV]	Voltage difference between rest and pulse end, in millivolts
Pulse resistance [mΩ]	DC internal resistance calculated as overpotential divided by mean pulse current

Pulse resistance metrics use step-level filtering to compare the voltage at the end of the initial rest period (step 0) with the voltage at the end of the current pulse (step 1).

6. Pseudo-OCV

Description: Measures the voltage profile at a very low C-rate to approximate the open-circuit voltage (OCV) vs. SOC relationship. The slow rate minimizes polarization effects. Adjustable Parameters:

Temperature [°C] - Operating temperature (default: 25°C)
Direction - ‘Charge’ or ‘Discharge’ (default: ‘Discharge’)
C-rate - Very slow rate to minimize polarization (default: 0.05C)

UCP Protocol

global:
    initial_temperature: input["Temperature [°C]"]
    initial_state_type: soc_percentage
    initial_state_value: ifelse(input["Direction"] == "Charge", 0, 100)

steps:
    - Control:
        set_variable:
            - name: VAR_IS_CHARGE
              eval: input["Direction"] == "Charge"
            - name: VAR_VMAX
              eval: input["Upper voltage cut-off [V]"]
            - name: VAR_VMIN
              eval: input["Lower voltage cut-off [V]"]
    - Direction[input["Direction"]]:
        mode: C-rate
        value: input["C-rate"]
        ends:
            # End of charge/discharge
            - Voltage > ifelse(VAR_IS_CHARGE == 1, VAR_VMAX, 1e9)
            - Voltage < ifelse(VAR_IS_CHARGE == 0, VAR_VMIN, -1e9)

Computed metrics:

Metric	Description
Capacity [A.h]	Absolute step capacity
Mean internal resistance [mΩ]	Absolute average internal resistance
Mean current [A]	Absolute average current

7. EIS (Electrochemical Impedance Spectroscopy)

Description: Applies small AC voltage perturbations across a range of frequencies to measure the complex impedance of the cell. Maps out kinetic and transport processes. Adjustable Parameters:

Temperature [°C] - Operating temperature (default: 25°C)
SOC [%] - State of charge for measurement (default: 50%)
Lower frequency [Hz] - Minimum frequency (default: 0.0001 Hz)
Upper frequency [Hz] - Maximum frequency (default: 10000 Hz)

UCP Protocol

global:
    initial_temperature: input["Temperature [°C]"]
    initial_state_type: soc_percentage
    initial_state_value: input["SOC [%]"]

steps:
    - EIS:
        lower_frequency: input["Lower frequency [Hz]"]
        upper_frequency: input["Upper frequency [Hz]"]

8. Cyclic Voltammetry

Description: Sweeps the cell voltage linearly between upper and lower limits at a controlled scan rate. Measures current response to identify redox reactions. Adjustable Parameters:

Temperature [°C] - Operating temperature (default: 25°C)
Scan rate [mV/s] - Rate of voltage sweep (default: 0.1 mV/s)

UCP Protocol

global:
    initial_temperature: input["Temperature [°C]"]
    initial_state_type: voltage
    initial_state_value: input["Lower voltage cut-off [V]"]

steps:
    - Control:
        set_variable:
            - name: VAR_SCAN_RATE_VS
              eval: input["Scan rate [mV/s]"] / 1000
    - Charge:
        mode: Voltage
        value: input["Lower voltage cut-off [V]"] + VAR_SCAN_RATE_VS * t
        ends:
            - Voltage > input["Upper voltage cut-off [V]"]
    - Discharge:
        mode: Voltage
        value: input["Upper voltage cut-off [V]"] - VAR_SCAN_RATE_VS * t
        ends:
            - Voltage < input["Lower voltage cut-off [V]"]

9. Cycle Aging

Description: Repeated charge/discharge cycles with capacity fade monitoring. Uses CCCV charge (constant current to voltage limit, then constant voltage to C-rate cutoff) and CC discharge with dual termination (voltage cutoff or depth-of-discharge capacity limit). Tracks capacity retention and can stop early when capacity falls below a specified percentage of nominal. Adjustable Parameters:

Temperature [°C] - Operating temperature (default: 25°C)
Nominal capacity [A.h] - Cell capacity for C-rate and DOD calculations (default: 5.0 A.h)
Charge C-rate - C-rate during CC charge phase (default: 1C)
Discharge C-rate - C-rate during discharge (default: 1C)
Depth of discharge [%] - Target DOD per cycle as % of nominal capacity (default: 100%)
Discharge voltage cutoff [V] - Minimum voltage to stop discharge (default: V_MIN)
Charge voltage [V] - Maximum voltage for CC/CV charge (default: V_MAX)
Charge C-rate cutoff - C-rate threshold to end CV phase (default: 0.05C)
Post charge rest time [s] - Rest after charge (default: 600 s)
Post discharge rest time [s] - Rest after discharge (default: 600 s)
Number of cycles - Maximum charge/discharge cycles (default: 100)
End capacity [%] - Stop cycling when capacity falls below this % of nominal (default: 80%)

UCP Protocol

global:
    initial_temperature: input["Temperature [°C]"]
    initial_state_type: soc_percentage
    initial_state_value: 50

steps:
    - Control:
        set_variable:
            - name: VAR_VMAX
              eval: input["Charge voltage [V]"]
            - name: VAR_VMIN
              eval: input["Discharge voltage cutoff [V]"]
            - name: VAR_NOMINAL_CAPACITY
              eval: input["Nominal capacity [A.h]"]
            - name: VAR_DOD_FRACTION
              eval: input["Depth of discharge [%]"] / 100
            - name: VAR_END_CAPACITY_RATIO
              eval: input["End capacity [%]"] / 100
            - name: VAR_CURRENT_CAPACITY
              eval: "0"
            - name: VAR_CAPACITY_RATIO
              eval: "1.0"
    - Control:
        set_variable:
            - name: VAR_DOD_CAPACITY_LIMIT
              eval: VAR_DOD_FRACTION * VAR_NOMINAL_CAPACITY
    - Cycle Block:
        repeat: input["Number of cycles"]
        steps:
            - Increment cycle number
            - Charge:
                mode: C-rate
                value: input["Charge C-rate"]
                resolution:
                    time: 10 / input["Charge C-rate"]
                ends:
                    - Voltage > VAR_VMAX
            - Charge:
                mode: Voltage
                value: VAR_VMAX
                resolution:
                    time: 10 / input["Charge C-rate"]
                ends:
                    - C-rate < input["Charge C-rate cutoff"]
            - Rest:
                duration: input["Post charge rest time [s]"]
            - Discharge:
                mode: C-rate
                value: input["Discharge C-rate"]
                resolution:
                    time: 10 / input["Discharge C-rate"]
                ends:
                    - Voltage < VAR_VMIN
                    - Capacity > VAR_DOD_CAPACITY_LIMIT
                set_variable:
                    - name: VAR_CURRENT_CAPACITY
                      eval: abs(last(Capacity))
            - Control:
                set_variable:
                    - name: VAR_CAPACITY_RATIO
                      eval: VAR_CURRENT_CAPACITY / VAR_NOMINAL_CAPACITY
            - Rest:
                duration: input["Post discharge rest time [s]"]
                ends:
                    - type: Variable
                      expression: VAR_CAPACITY_RATIO < VAR_END_CAPACITY_RATIO
                      goto: End Block
    - End Block:
        - Rest:
            duration: 1

Computed metrics:

Metric	Description
Total cycles	Number of completed charge/discharge cycles
Initial capacity [A.h]	Absolute discharge capacity from the first cycle
Final capacity [A.h]	Absolute discharge capacity from the last cycle
Capacity retention [%]	Ratio of final to initial capacity, expressed as a percentage
Total energy throughput [W.h]	Sum of discharge and charge energy over all cycles
Total charge throughput [A.h]	Sum of discharge and charge capacity over all cycles

Parameter Types

Standard Parameters

Most templates accept these common parameters:

Temperature [°C]: Operating temperature
Initial SOC [%]: Starting state of charge (0-100%)
C-rate: Current normalized by nominal capacity (e.g., 1C = full capacity in 1 hour)

Voltage References

Some parameters can reference cell-specific voltages:

V_MIN: Minimum safe voltage for the cell model
V_MAX: Maximum safe voltage for the cell model

These are automatically replaced with values from your selected cell model.

Direction

For bidirectional tests, specify ‘Charge’ or ‘Discharge’ to set the current direction.

Using Experiment Templates

In Simulations

Select a cell and model
Choose an experiment template from the “Start from existing protocol” dropdown
Adjust parameters as needed
Run the simulation

Creating Studies

You can run multiple experiments with different parameters in a study to:

Compare performance at different temperatures
Evaluate different C-rates
Map out behavior across SOC range

Next Steps

Create your own protocols with custom parameters
Learn more about Projects and Studies
Explore Simulations
Understand the Universal Cycler Protocol format

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Experiment Templates

Experiment Templates

Template metrics

Available Templates

1. Constant Current Discharge

2. Constant Current Charge

3. GITT (Galvanostatic Intermittent Titration Technique)

4. PITT (Potentiostatic Intermittent Titration Technique)

5. Pulse Resistance

6. Pseudo-OCV

7. EIS (Electrochemical Impedance Spectroscopy)

8. Cyclic Voltammetry

9. Cycle Aging

Parameter Types

Standard Parameters

Voltage References

Direction

Using Experiment Templates

In Simulations

Creating Studies

Next Steps

​Experiment Templates

​Template metrics

​Available Templates

​1. Constant Current Discharge

​2. Constant Current Charge

​3. GITT (Galvanostatic Intermittent Titration Technique)

​4. PITT (Potentiostatic Intermittent Titration Technique)

​5. Pulse Resistance

​6. Pseudo-OCV

​7. EIS (Electrochemical Impedance Spectroscopy)

​8. Cyclic Voltammetry

​9. Cycle Aging

​Parameter Types

​Standard Parameters

​Voltage References

​Direction

​Using Experiment Templates

​In Simulations

​Creating Studies

​Next Steps

Experiment Templates

Template metrics

Available Templates

1. Constant Current Discharge

2. Constant Current Charge

3. GITT (Galvanostatic Intermittent Titration Technique)

4. PITT (Potentiostatic Intermittent Titration Technique)

5. Pulse Resistance

6. Pseudo-OCV

7. EIS (Electrochemical Impedance Spectroscopy)

8. Cyclic Voltammetry

9. Cycle Aging

Parameter Types

Standard Parameters

Voltage References

Direction

Using Experiment Templates

In Simulations

Creating Studies

Next Steps