Google Maps, Apple Maps, PlugShare, and A Better Routeplanner all assume your EV charges at its advertised peak speed, drives at its EPA-rated efficiency, and fills up linearly like a gas tank. For a lot of real vehicles — conservative Battery Management Systems, no active preconditioning, an aging second-hand pack — none of that is true. ChargeCliff exists to show the physics those tools quietly assume away.
Owners of the Lexus RZ, Toyota bZ4X, Subaru Solterra, VW ID.4, Chevy Bolt, and any EV whose BMS prioritizes 10-year battery health over headline charging speed. If your car's real-world charging curve has ever made you feel lied to by its spec sheet, this is built for exactly that moment.
It's also a portfolio piece: a small, fully first-principles physics engine with every formula derived and every vehicle profile calibrated against a named, published benchmark — not a black box, and not a guess dressed up as one.
Every charge curve in this tool was tuned by running the actual Riemann-sum session simulation against a real published number — a factory dyno spec, a winter road test, a magazine's 75mph range test — and adjusting breakpoints until the model landed inside that published range. Those checks are pinned as automated regression tests, not a one-time claim: a future change that moves a result outside its published range fails the test suite.
A profile with no named benchmark (the Toyota bZ4X, Subaru
Solterra, and VW ID.4 today) is marked verified: false
in the API and flagged in the UI — a platform-sharing estimate,
presented with exactly the confidence it's earned, not more.
A DC fast-charge session integrated across discrete 1% State-of-Charge intervals — not a single kWh-divided-by-kW shortcut, because the charge curve genuinely isn't flat. Includes a cold-gating derate below 68°F and reports the exact SoC where sitting at the charger longer stops being worth it.
Aerodynamic drag scales with the square of speed; real highway cruising (70-75mph) plus a resistance-heater cabin warmer in cold weather can cut EPA-rated range 35-50%. Reports both the theoretical full-charge range and the standard 80%→10% SoC road-trip window everyone actually plans around.
A State-of-Health estimate from age and odometer alone — no OBD-II dongle, no manufacturer app — and the compounding power derate an aged pack's BMS applies on top of its own factory curve.
Per-minute billing charges the same rate regardless of how fast power is actually flowing, which means a slow-tapering EV can end up paying more per kWh — sometimes more per mile than gasoline — on the exact same billing plan as a fast-charging 800V car.