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QUALITY CONTROL PROCESS

Quality is not a terminal check.
It's a control logic embedded in every process.

Translating product requirements into CTQ, control plans, measurement methods, process capabilities, response plans and quality gates allows each key feature to have clear criteria, credible measurements and traceable control evidence throughout the process of arrival, manufacture, validation, release.

Real quality control is not the last question to be asked, but the control logic is put into the process before the problem arises.

Asking how to split into CTQ

Translating design requirements into detectable, measurable and enforceable process characteristics

128 Active CTQs
24 Safety-critical CTQs
Areas of request Design requirements (example) CTQ (key mass characteristics) Specifications/ Limit Values Measurement methods Frequency / Sample Quality / Responsible person
S
SAFETY Safety
Safety of personnel and equipment to meet electrical safety and quarantine requirements Insulation electrical resistance/ system protection ≥100 MΩ @1000VDC Insulation electrical resistance tester 100 per cent per unit Security Engineer
E
Electrical Electrical
The power lines are stable and reliable. Key Connection Twirl 35 ± 5 N·m Twisting system / Twisting 100% per point Process Engineer
T
Thermal management Thermal
Temperatures are controlled. Power core maximum temperature ≤30°C Temperature Sensors Network 100% per module group Heat Design Engineer
M
Mechanical Mechanical
Structure assembly and benchmarks to meet space requirements Area ≤1.0 mm / 2 m Laser meter 100 per cent per unit Structural Engineer
C
Communications Communication
Communications stability, data integrity Communication heart rate ≤0.1% Network analyser 100 per cent per unit Electrical control engineer
P
Process / Appearance Process
Welding, coating, appearance. Weld height 0.2 – 0.5 mm 3D visual meter 100 per cent per unit Quality Engineer
D
Delivery Delivery
Delivery documents and on-site transport status satisfied Packaging / Document Integrity No missing items Double check Each batch Delivery of engineers
View all CTQ registration forms

Stage Control Grid Control Plan Mesh . 9 controlled phases x multiple key control layers

Stage / Level Incoming Inspection
Incoming 		Model production
Module 		Pack
Pack 		Battery cupboard
Rack 		System Integration
System 		Electrical function testing
E/C Test 		FAT
FAT 		PSI
PSI 		Shipping
Shipment
Material identification
Material Identity		 ● ● ● ● ● ● ● ● ●
Process Parameters
Process Parameters		 ● ● ● ● ● ! ● ● ●
Product characteristics
Product Characteristics		 ● ● ● ● ● ! ● ● ●
Security Interlock
Safety Interlocks		 ● ● ● ● ● ! ● ● ●
Evidence Record
Evidence Records		 D D D D D D D D D
Release Permissions
Release Authority		 ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓
Checkpoint
Early warning / trigger
Unqualified / Stop Release
Let go!
Controlled: 9 Formal quality door: 8 Excessive release: 0

Validity of measurement systems

146 / 146 Calibration status effective.
18 / 18 MSA / GR&R
100% Data chain integrity
Instrument / Device ID Scale Resolution Calibration date MSA / GR&R Current Status
INS-000521 1 kΩ – 10 GΩ 0.1 MΩ 2025-07-18 GR&R 8.3% Valid.
TOR-000812 5 – 200 N·m 0.1 N·m 2025-06-02 GR&R 6.1% Valid.
PRD-000233 -5 – 5 kPa 1 Pa 2025-07-30 GR&R 7.0% Valid.
TMP-000654 -40 – 125°C 0.1°C 2025-08-15 GR&R 5.2% Valid.
PLC-000119 — — 2025-07-20 GR&R 3.6% Valid.
• Any calibration of measuring equipment that is out of date or not passed by the MSC automatically prevents the release of the relevant quality door.

Measuring system expansion Equipment and data links

QMS
Data platform
Insulation
Tester
Twisting.
Tools
Electrical
Test
Temperature
System
Leak.
Test
Visual
System

SPC Observatory Process capabilities, trends and abnormal signals

Insulated electrical resistance (M) Cpk 1.78
Busbar torque (N·m) Cpk 1.84
Battery bag leakage pressure reduction (kPa) Cpk 1.67
Container door gap (mm) Cpk 1.61
Insulation resistance trend
Temperature (°C)
Number of test cycles

Response plan engine Example: Battery bag leaking pressure exceeding limit

1
Test Trend Trigger
Result: 1.31 kPa
2
Auto-cut. Breakout test site stopped.
Autostop
3
Change of Status Device state to HOLD
HOLD
4
Accountability Offline / Offline
Quality engineer response
5
Segregation and screening Segregation of associated batches
Impact scope recognition
6
Mistreatment Create NCR
NCR-2504-0376
7
Root cause and correction Implementation of maintenance and correction
Corrective measures completed
8
Check. Retest
PASS
9
CAPA Closure and Release Reproduction verification complete.
CLOSED
Event period: 14.6 hours Number of impacts: 12 packages Associated work orders: WO-250612-1452 Status: Closed

Cross-level pass rate and closure result

One pass rate

99.68% Module
n=12,568
95.05% Pack
n=3,452
93.33% Rack
n=215
100% System
n=42
100% FAT
n=42

Quality closure result

Key NCR not closed 0
Overdue CAPA 0
Recovery rate after rehabilitation 100%
NCR number closed 86
Number of CAPAs closed 86

Trends in one pass rate Nearly 12 weeks

Quality assessment rhythm and upgrade

Dayline Review

Daily Line Review

  • SPC anomaly
  • Process capacity
  • NCR of the day
  • Cut-off matters
Responsibility: Group / Chief
Frequency: daily
Upgrade threshold: Red anomaly

Weekly quality review

Weekly Quality Review

  • Trends in quality
  • NCR / CAPA Status
  • Quantum and MSA
  • Significant risks
Responsibility: Quality Engineer
Frequency: weekly
Upgrading threshold: significant risk

Quality door review

Gate Review

  • Critical evidence integrity
  • NCR closed
  • Release Permissions
  • You must not overstep your authority.
Responsibility: Quality Manager
Frequency: Quality door
Upgrade threshold: release conditions not met

Management evaluation

Management Review

  • Quality targets achieved
  • Significant trends
  • Resource decision-making
  • System improvements
Responsibility: Management
Frequency: month/ season
Upgrade threshold: target deviation

Client / Project evidence package

Project Evidence Package

  • Delivery of evidence kits
  • Quality baseline
  • Final Release Record
  • Client requirements
Responsibility: Project Quality Manager
Frequency: Project delivery
Upgrading threshold: client requirements

Control plan evidence kit Full chain quality retroactive, verifiable

CTQ List of requirements CTQ registration form
128 CTQs
CURRENT
CP Control plan Control Plan
Phase 9
CURRENT
FMEA PFMEA Risk analysis
R04
CURRENT
MSA Survey system 146 Quantum sets
18 MSCs
VERIFIED
SPC SPC Records Process capacity
Trends
LINKED
RP Response plan Reaction Plan
Trigger Rules
ACTIVE
NCR NCR / CAPA Abnormal closed circle
0 OPEN
CLOSED
GATE Door review records Gate Review
100%
APPROVED
TRC Retroactivity and evidence Record chain
Package
TRACEABLE