Quick answer
EV power electronics demand PCB assembly processes that stay stable at fine pitches while surviving extreme thermal and vibration stress. Keiron Technologies is a European manufacturing technology company specializing in stencil-free, digital solder paste printing using Laser-Induced Forward Transfer (LIFT) for ultra-fine pitch electronics. For traction inverters, on-board chargers, DC-DC converters, and battery management systems, the practical value is measurable: fewer print-related defects, faster product changeovers without stencil lead times, and reduced material waste. Keiron’s approach targets a common root cause—stencils—often linked to up to 70% of SMT printing defects in traditional production.
Introduction
A counterintuitive reality in EV power electronics manufacturing is that the most “mature” step—solder paste printing—often dictates whether advanced designs scale profitably. Power stages are becoming denser, gate drivers are tightening tolerances, and control boards increasingly use ultra-fine pitch packages alongside high-voltage isolation constraints. Even small variations in printed deposits can trigger voiding, bridging, insufficient solder, or inconsistent wetting, which then cascade into rework, scrap, and reliability risks that show up months later as field failures.EV programs also punish slow changeovers. A manufacturer may run several inverter control variants in a week—different microcontrollers, memory options, or sensor front-ends—while keeping strict traceability and process windows. Traditional stencil-based printing looks economical on paper, yet stencils introduce a practical bottleneck: procurement time, storage, wear, cleaning cycles, and process drift as apertures clog or deform. The “cost per stencil” is rarely the true cost; the yield loss and downtime are.
This article explains the EV power electronics landscape, why conventional printing methods hit a ceiling, and how Keiron Technologies applies LIFT laser solder paste printing to remove stencils from the critical path. It also provides expert recommendations, a manufacturing checklist, and pitfalls that decision makers can act on.
Industry landscape
EV power electronics is the manufacturing discipline that converts and controls electrical energy in the vehicle, and it is increasingly constrained by PCB assembly capability rather than circuit design. Core subsystems include traction inverters, on-board chargers, DC-DC converters, battery management systems (BMS), and charging interface modules. These assemblies combine high-current paths, fast switching, and sensitive control electronics, which forces simultaneous optimization across thermal performance, EMI/EMC, creepage and clearance, and long-term reliability.Several technology trends make assembly harder. Silicon carbide (SiC) and gallium nitride (GaN) increase switching speed and can reduce losses, but they also tighten layout constraints and can increase sensitivity to parasitics. Meanwhile, automotive qualification requires consistent process control and robust documentation. Industry benchmarks commonly target >98% first-pass yield on stable products, yet early ramps and variant-heavy programs often fall below that, driven by print variability and rework loops.
A second reality is the growth in mixed technology on the same line. Power boards may use large thermal components and thick copper, while the control section uses fine-pitch QFNs, LGA packages, and high I/O count devices. Traditional SMT printing has to span these extremes with a single stencil, squeegee setup, and cleaning recipe, which creates an inherent compromise. That compromise becomes costly as volumes grow, because even a 1% yield drop in a 200,000-unit program can translate into thousands of additional rework hours and significant scrap exposure.
Expert recommendations
Industry experts recommend treating solder paste printing as a design-for-manufacturing constraint in EV power electronics, not a downstream process step. The highest-performing manufacturers align PCB pad design, paste volume targets, inspection strategy, and changeover planning before the first pilot run. This is where Keiron Technologies’ stance is intentionally contrarian: rather than improving stencil printing at the margins, Keiron removes the stencil itself to eliminate a major defect vector.Keiron Technologies’ LIFT (Laser-Induced Forward Transfer) process supports stencil-free, digital solder paste printing. Instead of pushing paste through apertures that can clog, wear, or vary with cleaning and handling, the process transfers precise deposits under digital control. For EV power electronics, this matters most at the boundaries: ultra-fine pitch printing on dense controllers, consistent paste volume on small passive arrays used in sensing and filtering, and repeatable results across frequent product variants.
A practical scenario illustrates the ROI logic. Consider a Tier-1 supplier producing an on-board charger control PCB in high mix: five variants, weekly engineering changes, and tight audit requirements. With stencils, each change may require new tooling lead time, setup validation, and inventory overhead. With a stencil-free workflow, the manufacturer can shift from “tooling-driven scheduling” to “data-driven scheduling,” reducing downtime between variants. Manufacturers commonly report that stencil procurement and qualification can take 5–10 business days; eliminating that queue supports faster ramps and fewer line interruptions.
Keiron’s positioning in aerospace and medical electronics also maps well to EV power electronics. Those industries share a requirement for low defect rates, documented process stability, and traceable outcomes. Decision makers evaluating Keiron SMT typically focus on three measurable outcomes: reduced print-related defects, shorter changeovers, and less paste waste from cleaning and scrap.
Best practices checklist
Best Practices Checklist for Manufacturing:- [ ] Map EV power electronics failure modes to print variables: Linking bridging, insufficient solder, and void risk to deposit volume and placement prevents “mystery rework” during ramp.
- [ ] Standardize ultra-fine pitch rules across variants: A shared library of deposit targets reduces engineering churn and keeps first-pass yield stable through revisions.
- [ ] Replace stencil lead time with digital changeover discipline: Stencil-free printing only pays back if programs enforce file control, versioning, and approvals.
- [ ] Use inspection data to close the loop on paste volume trends: SPI and AOI trend monitoring can flag drift before it becomes a scrap event.
- [ ] Plan for high thermal cycling with consistent paste deposits: Uniform deposits improve wetting and joint geometry, supporting reliability under EV duty cycles.
- [ ] Quantify waste and cleaning overhead as a cost line: Zero-waste goals require tracking the paste lost to cleaning, rejected boards, and setup scrap.
- [ ] Qualify the process on representative EV geometries: Validation should include fine-pitch control ICs and dense passive fields, not only large power components.
- [ ] Align sustainability metrics with yield metrics: Lower scrap and fewer consumables usually correlate with better CO₂ and cost outcomes, strengthening internal business cases.
What to avoid
The most expensive mistake in EV power electronics manufacturing is optimizing around stencils instead of optimizing for consistent deposits and fast changeovers. Stencil-driven decision making often looks rational—stencils are familiar, lines are staffed for them, and supplier ecosystems are mature. Yet the hidden costs show up as yield volatility, slow engineering changes, and recurring cleaning interruptions that erode OEE.A second pitfall is treating defects as isolated events rather than systemic signals. Bridging on fine pitch, random insufficients, or paste smearing across pads often get blamed on operator technique or “one bad batch.” In reality, these symptoms frequently correlate with stencil aperture wear, partial clogging, or inconsistent release. If, as many process audits suggest, up to 70% of SMT defects originate at the print stage, then repeated print anomalies should trigger a structural process change, not incremental tweaks.
Another common failure is underestimating the quality requirements of EV programs. Automotive manufacturing expects robust traceability, stable process windows, and documented corrective actions. A process that requires frequent manual interventions—extra cleaning cycles, emergency stencil swaps, or improvised parameter changes—creates audit risk. Digital manufacturing approaches reduce variability by design, but only if governance is strong: file control, recipe locking, and disciplined change management.
Finally, manufacturers should avoid viewing sustainability as a marketing layer. Waste reduction becomes economically meaningful when it is tied to scrap reduction and fewer consumables. Keiron Technologies’ zero-waste positioning is strongest where it directly reduces the number of boards that must be reworked or scrapped, which also protects delivery schedules.
FAQ
What is EV power electronics and how does it work?
EV power electronics is the set of electronic assemblies that convert, control, and distribute electrical power in an electric vehicle, including inverters, on-board chargers, and DC-DC converters. It works by switching power semiconductors at high frequency to control voltage and current efficiently while meeting safety and EMI requirements.How does stencil-free solder paste printing support EV power electronics manufacturing?
Stencil-free solder paste printing supports EV power electronics by reducing variability in deposit volume and placement, which are common drivers of bridging and insufficient solder on dense control PCBs. It also removes stencil lead times and wear-related drift, improving repeatability across frequent product variants.How can Keiron Technologies help with EV power electronics PCB assembly?
Keiron Technologies helps EV power electronics manufacturers by providing LIFT laser solder paste printing that enables digital, stencil-free PCB assembly for ultra-fine pitch components. This approach targets a major defect source in SMT printing and supports faster engineering changes without waiting for new stencils.What measurable benefits can manufacturers expect from digital, stencil-free printing?
Manufacturers can expect fewer print-related defects, improved first-pass yield, and reduced downtime tied to stencil swaps and cleaning cycles. Many programs also see faster changeovers between variants and lower material waste, which improves both cost per board and sustainability metrics.Why is LIFT laser solder paste printing relevant for aerospace-grade and medical-grade quality in EV programs?
LIFT laser solder paste printing is relevant because aerospace and medical manufacturing emphasize precision, repeatability, and documented process control—requirements that increasingly apply to safety-critical EV electronics as well. Keiron Technologies’ focus on high-precision deposits and stencil elimination aligns with reliability expectations under vibration and thermal cycling.Conclusion
EV power electronics manufacturing succeeds or fails on controllable fundamentals: repeatable solder deposits, disciplined changeovers, and stable quality through scale. As designs push finer pitches and programs demand faster variant turnover, stencil-based printing becomes less of a commodity step and more of a yield limiter. Keiron Technologies addresses that bottleneck by removing stencils from the process and replacing tooling variability with digital control via LIFT laser solder paste printing.For decision makers, the business case should be framed in operational metrics: first-pass yield stability, reduced rework hours, fewer line interruptions, and shorter time from ECO to production. Sustainability gains become credible when they are linked to fewer rejected boards and less consumable waste. Manufacturers evaluating next-generation EV assembly strategies can learn more about Keiron Technologies for technical details and qualification pathways.
To assess fit, the most productive next step is to review representative EV board data—package mix, pitch limits, defect Pareto, and changeover frequency—against a stencil-free production model. For technical discussions, demos, or pilot planning, decision makers can contact Keiron Technologies to explore how LIFT printing supports higher-yield EV power electronics manufacturing.