voltage sag

Articles, guides, and products tagged "voltage sag" — a combined view of every catalogue resource on this topic.

User guide

Climbing hills on an electric scooter: gradeability, torque, motor overheating, dual-motor, and common mistakes

What gradeability actually means in escooter specs and why 30 % ≠ 30°. How manufacturers test under bench conditions and why your real numbers with a 90 kg rider are lower. Why torque (Nm) — not power (W) — determines climbing ability. The difference between geared-hub and direct-drive at low RPM, and when dual-motor is worth it. Thermal limits of BLDC motor windings (~115 °C) and MOSFET controllers (~80–100 °C). Voltage sag, the 20 % SOC rule, LVC cutoffs, and why cold weather doubles the penalty. Practical riding — pre-hill momentum, walk-assist mode, when to dismount. Real-world numbers from five platforms (Xiaomi 4 Pro, Segway-Ninebot Max G30, Apollo Phantom V3, Kaabo Wolf Warrior 11, Dualtron Storm) plus 7 common mistakes.

13 min read

User guide

Used electric scooter: pre-purchase inspection checklist

Structured 11-axis pre-purchase inspection of a second-hand electric scooter: paperwork and serial-number checks (proof of purchase, cross-check against the Xiaomi M365 June 2019 recall — 10,257 units, serials 21074/00000316–21074/00015107 and 16133/00541209–16133/00544518, manufactured 27 Oct – 5 Dec 2018), stolen-goods lookup (UK BikeRegister — Met Police-approved, 1.3M+ bikes registered, free BikeChecker; US Bike Index — 1.4M+ registrations, free), battery as 30–50% of residual value (Battery University BU-808: 300–500 cycles at 4.20 V/cell vs 1,200–2,000 at 4.00 V/cell; BU-808b — voltage stress and SEI growth; SOH via voltage sag under load, capacity test via full charge–discharge; visual cues — swelling, terminal corrosion, thermal marks), fire risk (CPSC 2019–2023: 227 incidents, 39 fatalities, 181 injuries), folding stem (Xiaomi M365 recall), motor and controller (bearing noise, error history on display), brakes (pad thickness, rotor warping, hydraulic line check), tires (NHTSA 49 CFR 574.5 — DOT 4-digit code, first two = week, last two = year; tread depth), lights/IP/connectors (corrosion), test ride (full-charge → load → discharge curve), negotiation red flags (missing serial, no charger, evasive seller, “battery just replaced” without invoice), post-purchase (firmware update, re-registration on BikeRegister/Bike Index).

14 min read