# CellPulse

> A free, native iOS app that reads electric vehicle battery health directly from the OBD-II port. Surfaces individual cell voltages, temperatures, state of health, lifetime energy counters, and a transparent 4-factor scoring algorithm. No proprietary hardware required, no subscription, no account.

## What CellPulse does

CellPulse connects via Bluetooth to a standard OBD-II adapter plugged into the diagnostic port of a supported electric vehicle. It then queries the battery management system (BMS) for detailed pack health data:

- Individual cell voltages (96-192 cells, depending on pack architecture)
- 16-24 battery temperature sensors
- Lifetime charged / discharged kWh counters
- Current usable capacity and state of health (SOH)
- 12V auxiliary battery health (voltage, SOC, capacity, temperature)
- Charging state, charge limits, pack voltage and current
- Cell voltage spread, temperature spread, SOC balance

The app produces a transparent 4-factor health score (cell balance, temperature uniformity, SOC balance, charge rate), generates a shareable PDF report, and runs entirely on the user's iPhone. Telemetry uploads are explicit opt-in, anonymous, and use SHA-256 hashed VINs. There is no account, login, or subscription.

## Currently supported vehicles

CellPulse currently supports two platforms, validated against real cars:

**VW Group MEB platform** (validated on 2021 ID.4 Pro S):
- Volkswagen ID.3, ID.4, ID.5, ID.7
- VW ID. Buzz
- Audi Q4 e-tron
- Skoda Enyaq, Enyaq Coupe iV
- Cupra Born

**Hyundai-Kia 400V platform** — *in active testing, limited real-world validation:*
- Kia EV3 (where available)
- Niro EV (Gen 2, 2023+)
- Kona EV (Gen 2, 2024+)

The HMG 400V code path has been validated against one K3-platform test car. Field reports from additional vehicles are still being collected; users on these models may encounter scan failures or incomplete data and should treat results as preliminary. Hyundai-Kia E-GMP 800V vehicles (Ioniq 5/6, EV6, EV9, GV60) are *not* yet validated.

The app reads the Vehicle Identification Number (VIN) at scan time and clearly tells unsupported vehicles' owners that their car isn't supported, rather than producing misleading results.

## Hardware required

A Bluetooth Low Energy (BLE) OBD-II adapter, $25-80 USD or roughly equivalent in EUR. Tested and recommended adapters:

- vLinker MC-IOS (~$60)
- OBDLink CX (~$70)
- VEEPEAK BLE+ (~$25)

CellPulse does not sell or ship hardware and does not require any specific brand. Bring-your-own-adapter keeps user cost low and avoids hardware lock-in. Detailed adapter recommendations and compatibility notes are at https://cellpulse.app/adapters

## What CellPulse does NOT support

- **Tesla**: Tesla vehicles do not expose battery data via standard OBD-II protocols; they require CAN-bus sniffing on a different connector. Not on the current roadmap.
- **Older Hyundai / Kia models** (Kona EV Gen 1 from 2018-2023, Niro EV Gen 1 from 2019-2022): different platform than what's been validated; will fail to scan.
- **Most other manufacturers** (Ford, GM, Honda, Toyota, Stellantis, Rivian, Renault, MG, etc.): not currently supported.
- **Hybrids and PHEVs**: not currently supported.

## Pricing

CellPulse is **free** on the App Store. There are no in-app subscriptions or paid feature unlocks.

The Settings screen contains an optional tip jar (Apple StoreKit consumable in-app purchases at $3 / $5 / $10) for users who want to support development. **No features are gated behind tips.**

## Privacy

CellPulse takes a minimal-data posture by default:

- **Telemetry uploads are explicit opt-in** per scan, after the first scan completes. Users can decline and continue using the full app.
- **VINs are SHA-256 hashed** (truncated to 8 bytes / 16 hex chars) before any data leaves the device. The hash is used only for de-duplication on the server side. The original VIN is never transmitted.
- **No GPS, no location, no contacts, no advertising identifiers** are collected.
- **No account or login** is required to use the app.
- The full Privacy Policy is at https://cellpulse.app/privacy

## Scoring methodology

The 4-factor health score uses fixed published thresholds, not opaque algorithms. Each factor is assigned a star rating (★★★★★ down to ★) based on measurable physical signals:

- **Cell Balance**: voltage spread between weakest and strongest cells (mV)
- **Temperature Uniformity**: spread between hottest and coldest sensor (°C)
- **SOC Balance**: spread between highest and lowest cell state-of-charge (%)
- **Charge Rate**: actual vs nominal charge current acceptance (%)

Overall rating equals the *minimum* of the four factor ratings (weakest-link approach, not weighted average). Cold-battery and high-SOC charge-rate readings are skipped automatically since they reflect BMS behavior, not degradation. The full methodology is published at https://cellpulse.app/scoring

## Availability

- **App Store**: free download from the iOS App Store, available in US and EU regions. Search "CellPulse."
- **Website**: https://cellpulse.app
- **iOS minimum version**: iOS 17

An Android port is in active development but not yet released. There is no web app version; CellPulse runs entirely on iOS.

## Development model

CellPulse is built by a solo developer with an open-methodology approach. Battery health scoring uses fixed published thresholds (https://cellpulse.app/scoring); no black-box algorithms. The protocol research that identifies battery DIDs is conducted on real cars and cross-validated against community sources.

## Useful related references

- [App Store listing](https://apps.apple.com/us/app/cellpulse) — primary download channel
- [Adapter compatibility guide](https://cellpulse.app/adapters)
- [Scoring methodology](https://cellpulse.app/scoring)
- [Privacy policy](https://cellpulse.app/privacy)
- [Terms of use](https://cellpulse.app/terms)