TPMS Battery Welding Work Instruction
This work instruction turns TPMS battery welding from operator-dependent practice into an authorized, verifiable and traceable process. The public version defines control logic; equipment programs and release limits must come from the actual material combination, process validation, customer requirements and project control plan.
Scope and document boundary
Applies to approved tabbed cells, cell-to-tab joining, tab forming and related tab-to-PCB connection work.
Only personnel trained and authorized for safety, ESD, equipment, quality criteria and abnormal handling may perform the work.
The cell, tab, PCB, drawing, BOM, equipment program, fixture, electrodes, inspection specification and control plan must be current approved revisions.
Appearance or pull strength alone does not prove system reliability; contact resistance, pulse sag, EOL and required reliability evidence are also needed.
Pre-start condition checks
| Check item | Requirement | Stop condition |
|---|---|---|
| Documents and work order | Confirm the work order, product, BOM, drawing, WI, control plan and equipment program revisions match; complete line clearance. | Do not start when product or revision identity is inconsistent. |
| Cell and tab | Check supplier, model, lot, date, storage status, polarity, tab material, plating, thickness and surface cleanliness. | Mixed lots, wrong polarity, oxidation, contamination, deformation or expired material are not permitted. |
| Equipment and fixture | Confirm calibration, locked program, fixture revision, force system, cooling, alarms and data acquisition are available. | Stop for wrong program, expired calibration or unresolved alarms. |
| Electrodes and safety | Check electrode material, face, wear, cleanliness and alignment; confirm short-circuit protection, eye protection, ESD and lithium-cell abnormal-response provisions. | Do not use burned, offset, contaminated or end-of-life electrodes. |
Standard operating steps
Clear the line and verify material
Count cells, tabs and PCBs against the work order, isolate unrelated material and record critical lot identities.
Call the controlled program
An authorized operator selects the locked program matched to the product, material stack and fixture. Similar-product parameters must not be substituted.
Load with polarity mistake-proofing
Locate the cell and tab against defined datums; verify polarity, stack direction, weld position, insulation clearance and anti-reversal controls.
Produce first-off welds
Make the specified first-off quantity and review equipment curves, alarms, expulsion, indentation, weld position and cell-seal condition.
Approve the first piece
Complete appearance, dimensions, joint strength and failure mode, four-wire resistance and required pulse-load checks.
Run controlled production
After approval, monitor program, force, electrodes, weld appearance, location and process signals at the control-plan frequency.
Form tabs and transfer
Use the specified direction and bend radius so the weld nugget and cell seal do not become secondary bend points; maintain short-circuit clearance.
Complete EOL and lot release
Link polarity, static voltage, sleep current, wake-up, pulse sag, RF/EOL and audit records to the serial number or batch.
Critical process control table
| Control item | Critical input | Operating requirement | Retained evidence |
|---|---|---|---|
| Program and energy | Equipment program, waveform, current or energy, pulse time and monitoring limits | Use only the validated approved program; any adjustment requires authorization and renewed first-piece approval. | Process curves, alarms and first-piece record |
| Electrode system | Material, face, force, alignment, cleanliness, wear and replacement life | Clean and confirm at the defined frequency; replace for end of life, offset wear or burning. | Electrode maintenance record |
| Stack and location | Polarity, tab direction, overlap, weld location and distance from the cell seal | Use mechanical or vision mistake-proofing rather than operator memory. | First-piece image or dimensional record |
| Appearance and heat effect | Expulsion, burn-through, cracks, abnormal indentation, plating damage, insulation damage and seal deformation | Stop and isolate immediately; cosmetic rework cannot replace root-cause confirmation. | 100% appearance confirmation and nonconformance record |
| Joint performance | Pull or shear result, failure location, four-wire contact resistance and pulse voltage sag | Evaluate both value and failure mode; static low resistance does not replace real transmit-load testing. | Sampling, destructive audit and trend |
| Tab forming | Bend location, direction, radius, preload and stress at the PCB connection | Do not create a secondary bend at the nugget, cell seal or PCB joint. | Forming first-piece and patrol record |
First-piece, patrol and periodic audits
| Inspection level | Check content | Trigger or frequency | Release rule |
|---|---|---|---|
| 100% operation check | Material identity, polarity, program, location, weld appearance, insulation clearance and equipment result. | Every part / automatic or manual mistake-proofing | Nonconforming parts cannot transfer. |
| First-piece inspection | Appearance, dimensions, pull or shear, failure mode, four-wire resistance and project-defined dynamic checks. | Start of shift, lot or model change, program or electrode change, repair or restart | Production begins only after authorized approval. |
| Process patrol | Equipment curves, force, electrodes, weld location, expulsion, tab forming and process trend. | Control-plan frequency | Trace back to the last accepted point after an excursion. |
| Periodic destructive audit | Nugget, section, strength, failure mode and electrode-life boundary. | Based on product risk, volume and control plan | Confirms the process window remains effective. |
| EOL system validation | Polarity, static voltage, sleep current, wake-up, pressure and temperature reading, RF transmission and traceability binding. | Product EOL specification | System failures cannot be packed or released. |
| Reliability audit | Cold pulse load, thermal cycling, vibration, mechanical shock, centrifugal load and pre/post-aging comparison. | Validation plan and change risk | Confirms long-term margin in the target environment. |
Abnormal handling and rework limits
| Abnormal condition | Immediate action | Restart boundary |
|---|---|---|
| Equipment alarm, signal excursion or wrong program | Stop, lock the program, isolate work since the last accepted check and notify engineering and quality. | Do not restart before cause confirmation and a new first piece. |
| Expulsion, burn-through, abnormal indentation or seal deformation | Stop and inspect electrodes, force, location, contamination and program selection; retain failed samples. | Grinding or rewelding does not authorize release. |
| Strength, failure-mode or resistance failure | Isolate the lot and related time window, verify fixture and test method, then perform tightened validation and impact review. | Do not respond only by increasing welding energy. |
| Wrong polarity, short circuit or insulation damage | Control the safety risk, isolate under the lithium-cell response procedure and trace the mistake-proofing failure across the lot. | Affected cells must not be reused. |
| Rework request | Use only an approved rework specification that evaluates added heat input, weld location and cell-seal risk; record count and approval. | Without a validated rework route, treat the part as nonconforming. |
Release records and change control
| Record category | Minimum retained content |
|---|---|
| Lot traceability | Work order, product, serial or lot, cell, tab, PCB, housing and potting-material lots. |
| Equipment traceability | Machine, program revision, fixture, electrode, calibration, maintenance, cleaning, replacement and process curves. |
| Personnel traceability | Operator, first-piece approver, patrol inspector, abnormal reviewer and release authority status. |
| Quality evidence | Appearance, dimensions, strength, failure mode, contact resistance, pulse sag, EOL and reliability results. |
| Change control | Cell, tab, plating, equipment, program, electrode, fixture, PCB, solder, housing, potting and EOL-software changes. |
Frequently asked questions and references
Frequently asked questions
Do not apply a soldering iron directly to a standard cell case unless the cell supplier has explicitly approved the cell structure and process. Use supplier-approved tabbed cells or a validated joining route.
Cell case, tab material and thickness, electrodes, equipment, fixture and product structure all change the process window. Copying another product’s values can cause weak joints, burn-through or seal damage.
No. Failure mode, contact resistance, real pulse load, EOL and required environmental and mechanical evidence must also be considered.
Only under a validated approved rework specification. A second weld adds heat and mechanical risk and is not a default recovery method.
Reference basis
To convert this public framework into a product-specific controlled WI, parameter validation, PFMEA, control plan or abnormal analysis, submit the cell, tab, equipment, fixture, PCB, package and validation requirements.
Submit TPMS battery welding review inputsResource Scope and Project Inputs
This module helps readers convert website guidance into reviewable RFQ and project inputs for XSD Precision engineering communication.
Who This Resource Is For
TPMS sourcing, service, channel and engineering teams confirming OE numbers, vehicle year and market, frequency, programmable-sensor coverage and vehicle relearn validation boundaries.
Project Inputs
OE number, vehicle year, target market, 315MHz / 433MHz frequency, programming tool, sensor sample, activation/read results and relearn conditions.
How XSD Precision Uses This Information
The website explains decision logic, input checklists, validation paths and collaboration methods. Vehicle programs, test records, software details, quality records and project confirmation materials are reviewed through direct project communication.