Smart BMS + External Cell Balancer for 12S-18S LiPo / LiHV Packs (PCB + Firmware)

PLEASE READ BEFORE YOU BID - Read this post and both attached spec PDFs fully before you bid. - We are looking for PCB designers. BMS experience is a big plus. - In your bid, give a short basic understanding of this project in your own words. - Bids with general text will not be selected. The project We need a BMS for our own 12S, 14S and 18S LiPo / LiHV battery packs (cells up to 30 Ah, pack 30-80 V). This is 1 project with 2 PCB works. A detailed spec PDF for each work is attached. Work 1: BMS board + optional cut-off module (inside the pack) - Monitors every cell (≤10 mV) and measures current through an off-board shunt (0.5-400 A, no overflow to 800 A for 3 s). - Balances at about 100 mA per cell, counts charge, keeps a log, shows charge on 5 green LEDs. - Talks over isolated CAN (DroneCAN), plus Bluetooth on one model. - USB port (micro USB, USB-C or similar) to write firmware and copy logs / data to a PC. - No pack current flows through the board. One PCB makes all models by fitting or leaving out parts. - An optional cut-off module plugs into the board: - 363 A continuous, 800 A for 3 s, 150 A charge - pre-charge and a hardware short-circuit trip - it never cuts flight power except on a short Work 2: External cell balancer (at the charging place) - 18 channels at about 1 A per cell, each switched on its own; heat stays outside the pack. - USB port (micro USB, USB-C or similar) to write firmware and copy logs / data to a PC. - Two modes, chosen by which input the pack is plugged into: - BMS mode: our BMS controls it over CAN and an enable pin. - Standalone mode: it serves other packs through a standard balance lead, with its own ≤10 mV readings, cell count check and stops. The two works share the balance connector, the enable pin and the CAN message set, so one designer keeps them matched. Deliverables for each work - Schematic, PCB, BOM and Gerbers. - Full firmware source with build steps. - Protocol documents (Bluetooth / CAN; balancer messages). - A PC tool for testing, firmware writing and log / data copy over USB. - Test and calibration procedure, and a test report. You choose all parts: branded, with steady supply and a datasheet. In your bid, tell us 1. Your basic understanding of this project, in your own words. 2. Your PCB design experience, with 2-3 boards you designed (pictures or links). 3. Your plan and time for Work 1 and for Work 2. 4. Any question you have about the spec.