Behind The Hardware: Our 240kW DC Charger Design Journey
From prototype on a bench to ARAI-certified mass production — the story of our most popular charger model.
Why We Built The 240kW From Scratch
In 2024, our first Chargeonix™ 120kW charger was already deployed at 80+ sites. But our site partners kept saying the same thing: 120kW is perfect for mid-day cabs, but highway SUV drivers need 240kW minimum. Imported EU and Chinese 240kW units had two fatal flaws for Indian conditions: (1) they derated to 120kW output above 45°C ambient — which is 6 months of the year across most of North India — and (2) service lead times for spares were 60+ days because components were not stocked locally. So we decided to build our own, 100% Made-in-India, from the power stage up.
Silicon Carbide + Optimized Air Cooling
Our R&D team picked SiC (Silicon Carbide) MOSFETs from the start — switching losses are 65% lower than IGBTs at 40 kHz, which means smaller heat sinks and higher overall efficiency (96.8% peak vs the 94% industry average). Crucially, we designed a modular cooling array with three independent fan zones. At ambient up to 52°C, the charger maintains full 240kW output without thermal derating. We stress-tested this in our Jhotwara lab for 4,200 continuous hours at 55°C — and passed ARAI Type Approval on the first attempt.
The BMS Handshake Problem
One of the hardest parts of designing a charger is the 'BMS handshake.' Every OEM's battery management system speaks a slightly different dialect of the CCS2/ISO 15118 standard. We bought 11 different EV models — Tata Nexon EV Long Range, MG ZS EV, BYD Atto 3, Mahindra XUV400, Hyundai Kona, Kia EV6, Audi Q8 e-tron, and more — and ran 400+ charge sessions, logging every CAN frame. We then built a compatibility matrix into our charger firmware with adaptive fallback logic. Result: Chargeonix™ 240kW is the only charger in its class with a documented 100% first-try connect rate across all 34 4-wheeler models sold in India today.
ARAI Certification & Field Pilot
ARAI Type Approval for DC chargers covers 48 tests: environmental (dust, IP55 rain, vibration, salt fog), electrical (isolation resistance, dielectric, over/under-voltage, short-circuit), and interoperability. Our prototype passed in 11 weeks. We then ran a 6-month pilot with 8 units at petrol pumps on NH48 (Delhi–Jaipur–Ajmer) and NH8 (Ahmedabad–Mumbai stretch). Average uptime across the pilot: 99.62%. Average session count per day per charger: 9.4 — beating the 7/day industry average.
Mass Production & The Road Ahead
Our 240kW chargers are assembled in our Jaipur facility (250 units/month capacity, scaling to 800/month in Q4 2026). For 2027, we are working on the 240kW Gen-2: 10% lighter, 97.4% peak efficiency, 480kW dynamic bus-bus capability, and native OCPP 2.0.1 support. The Gen-2 platform will also be the base for our 240kW dual-gun charger launching Q1 next year.