Battery Test & Diagnostics Engineer

Position Title:              Battery Test & Diagnostics Engineer

Duration:                      Contract

Location:                      Banbury, Oxfordshire.

Our Client is seeking a technically capable Battery Test & Diagnostics Engineer to support high-voltage battery and power-system commissioning, diagnostics, validation and engineering fault resolution. This hands-on role supports prototype and production build phases, with PEOL/EOL testing providing the environment for proactive engineering investigation rather than routine test execution alone. The engineer will independently isolate complex failures, test engineering hypotheses and drive corrective action across battery hardware, BMS, electrical interfaces and test systems.

Key Responsibilities

Diagnose HV battery pack, BMS and power-system faults covering contactors, pre-charge circuits, HVIL, insulation monitoring, voltage/current sensing, thermal management and control interfaces. Interpret electrical schematics, CAN/XCP logs, diagnostic codes, oscilloscope traces and DAQ measurements to isolate hardware, software, calibration, network or test-equipment faults. Own systematic fault investigations from symptom reproduction and hypothesis development through root cause confirmation, corrective action and verification of resolution. Apply structured RCA methods including 5 Whys, 8D and fault-tree analysis; investigate intermittent, repeatable and operating-condition-dependent failures. Develop and perform controlled fault-injection and abnormal-condition tests to verify BMS diagnostics, fault detection thresholds, protective actions, interlocks and recovery behaviour. Use approved risk assessments, authorised equipment and safe test methods for all HV and fault-injection activities. Execute and technically assess PEOL/EOL commissioning and performance tests; investigate failed results rather than simply repeat or reset test sequences. Distinguish genuine product failures from false failures, test-rig limitations, incorrect limits, communications faults and calibration issues. Analyse trends in test data, identify recurring defects and recommend improvements to test coverage, test limits, diagnostic methods and production robustness. Develop or adapt diagnostic routines, test scripts, data acquisition and engineering test procedures to support investigation and validation. Work with battery design, BMS software, validation and manufacturing engineering teams to agree engineering fixes and verify their effectiveness. Produce clear test evidence, technical investigation reports, root-cause findings and practical recommendations; proactively escalate safety or delivery risks.

Key Requirements:

Strong hands-on engineering experience with HV battery packs, battery management systems or closely related EV energy-storage and power systems. Proven ability to independently fault-find complex electrical, electronic and system-level issues and deliver evidence-based root cause analysis. Sound understanding of battery pack architecture, contactors, pre-charge, HVIL, insulation monitoring, sensors and BMS fault/protection strategies. Practical experience in fault injection, diagnostic validation, abnormal-condition testing or equivalent controlled fault simulation. Competence interpreting wiring diagrams, electrical schematics, system architectures, CAN signals and diagnostic data. Experience using oscilloscopes, multimeters, DAQ systems and CAN/XCP tools such as Vector CANoe, CANalyzer or CANape. Ability to analyse data, develop diagnostic hypotheses, challenge test outcomes and independently drive technical problems to closure. Formal HV training, safe-isolation competence and disciplined adherence to HV safety procedures and risk controls. Degree, HND or equivalent relevant experience in Electrical, Electronic, Automotive, Mechatronics or Systems Engineering.

Tools & Knowledge (Desirable):

Lithium-ion battery module/pack validation, thermal management and BMS calibration experience. PEOL/EOL test development and engineering support in prototype, low-volume or production EV environments. Test scripting and automation using Python, MATLAB, LabVIEW or similar tools. Knowledge of DFMEA, DVP&R, fault coverage, diagnostic thresholds and software/hardware integration.

Candidate Profile:

A proactive, technically inquisitive engineer who does not stop when an EOL test reports a failure. The successful candidate can explain why the system failed, safely reproduce and isolate the issue, establish the root cause and drive an effective engineering resolution.

Why Work Through Contechs?

Contechs is a leading Automotive, Design, Engineering, Technology and Innovation Recruitment Consultancy. Founded in 1997, with an in-house Contractor Care Team to support all external employees, Contechs acts as an employment agency for permanent and contract recruitment.

How to Apply

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