> ## Documentation Index
> Fetch the complete documentation index at: https://docs.ionworks.com/llms.txt
> Use this file to discover all available pages before exploring further.

# 2025 12 15

<Update label="December 15, 2025" description="Redesigned design optimization API and voltage components plot">
  ## Redesigned design optimization API

  Design optimization has been restructured with a cleaner API for configuring models, parameters, experiments, and objectives. A new strict schema enforces valid configurations and enables automatic frontend form generation, making it easier to set up and validate optimization runs.

  [Find out more →](/optimize/overview#design-optimization)

  ## Voltage components plot

  A new voltage components plot lets you visualize the individual contributions to cell voltage — such as open-circuit voltage, ohmic losses, and reaction overpotentials — for deeper insight into cell behavior during simulations.

  <AccordionGroup>
    <Accordion title="Studio">
      **Fixes**

      * Fixed cells from other projects appearing in cell selection lists.
      * Empty simulation data now correctly shows a failed status instead of a blank result.
    </Accordion>

    <Accordion title="Pipeline">
      **Fixes**

      * Fixed reaction overpotential (eta\_r) calculation bug.
    </Accordion>
  </AccordionGroup>
</Update>