Table of Contents
Assignment background
In the battery structure of an EV (electric vehicle), the mating surface between the cover and tray is an important joint that requires waterproof, dustproof, and vibration-resistant performance. Applying a liquid gasket to this joint ensures airtightness, but this poses the following challenges:
- Variation in coating width and thickness
When applying the sealant manually or using simple devices, it is difficult to maintain a consistent track width and height, resulting in uneven sealing. - Defects caused by stringiness and dripping
Highly viscous liquid sealants tend to become stringy after application, and there have been cases where the liquid spills out of the adhesive line before solidifying. - Increased man-hours for corrections and rework
In areas where the film was too thin or where the line was broken, frequent reapplication and repairs were required, reducing productivity.
Benefits
The introduction of the vipro-PUMP series (large capacity type) into the EV battery pack sealing process has resulted in the following benefits:
- Achieves uniform line width and film thickness with ±1% high-precision, quantitative coating
Rotating volumetric dispenser ensures consistency without being affected by viscosity or temperatureConstantly stable flow controlThis is difficult to do manually or with simple devices.Formation of uniform coating tracksThis has resulted in improved reliability of the sealing section. - Reduces stringiness and dripping, reducing product defects
High response and liquid cut-off of discharge control,The start and end points of application are beautifully finished.With thatEliminates pooling and overflow at the gasket edgeThere was no variation in the seal width, and product yield improved significantly. - Reduced remediation and increased productivity
Previously, this was a frequent occurrence.Almost no need for reapplication or repairsThis reduces the burden on workers. The coating process is becoming more automated and standardized.Improving productivity across the entire linecontributed to. - Stable application for long periods of time even on high viscosity and filler-containing materials
It also supports ultra-high viscosities up to 2,000,000 mPa・s.Stable and continuous long-term discharge even with filler-containing and abrasive liquidsEven large workpieces such as EV battery packs can be machined with this technology.Uninterrupted, tightly sealed application linesforms.
Application process video also available
Introduced products
vipro-PUMP series dispenser (large capacity type)
The vipro-PUMP is a rotary volumetric dispenser that can handle high-viscosity liquid gasket materials containing fillers. The large-volume model allows for continuous, stable dispensing even for large EV parts. • Dispensing accuracy within ±1% with a volumetric transfer system
- Also compatible with fillers and abrasive liquids
- Supports ultra-high viscosities up to 2,000,000 mPa・s
- Formation of a continuous coating line strengthens the sealing performance of the liquid gasket

