Methodology Validation

How Certvolt scores compare to Tesla's own test.

We compute battery health from telemetry. Tesla's service center can run an official battery health test in service mode. They're measuring different things — but they should agree closely on capacity retention. This page is where we publish the agreement (or disagreement) between the two, validated by owners who submit their Tesla test result.

Building the validation set

We have 0 of 10 submissions needed before publishing aggregated validation stats. We're not publishing partial stats — small-N comparisons are misleading. As soon as we hit the threshold this section will fill with real numbers.

How to submit your Tesla test result

If you've had a battery health test run at a Tesla Service Center (or via the Tesla app "Battery Health Test"), we'd love to publish the comparison anonymously.

  1. Open your Certvolt dashboard while logged in.
  2. Find the Battery tab → scroll to the "Submit a Tesla test result" card (coming).
  3. Enter the result Tesla gave you (numeric % or healthy/degraded label).
  4. Submit. Your VIN stays private; only the (Certvolt, Tesla) percentage pair is aggregated here.

What we'd expect to see

  • Mean diff near 0% — if Certvolt systematically over- or under-estimates capacity, this number reveals it.
  • RMS error under 3% — would indicate Certvolt's daily-snapshot inference closely matches Tesla's direct measurement.
  • >80% within 5% — would indicate Certvolt is a reasonable proxy for the Tesla test for owners who can't easily get one.

We don't pre-publish guarantees. The numbers above are what they are once enough owners submit. If Certvolt disagrees with Tesla in patterns we don't expect, that'll show up here too — that's the point.

Why this exists

r/teslamotors and TMC threads regularly ask "is third-party battery analysis just guesswork?" The honest answer: it's an inference from displayed range and EPA spec, not a direct cell measurement. But that doesn't mean it's wrong — it means we should validate against a direct measurement (Tesla's service-mode test) and publish the results, including the disagreements.

Privacy: Submissions are stored with your VIN (so we can match the Certvolt score to your Tesla test) but the aggregated stats above never include your VIN, your name, your location, or any individual data point identifiable to you. Only the (Certvolt %, Tesla %) pair appears in the scatter sample, and only when ≥10 pairs exist.