Stop Crushing Your Battery Cells: A Better Way to Press
Let’s be honest: pressing battery cells during packaging is a bit of a gamble. If your materials are too stiff, you’re basically playing Russian roulette with the internal structure. One wrong move and you’ve got a deformed cell or, worse, an internal short. That’s why we started using Near-Infrared (NIR) preheating. Instead of just slamming the press down on cold materials, we use NIR to warm things up first. It softens the adhesives and the packaging films just enough so that when the press hits, the materials give way. You don’t need nearly as much force, which means the guts of the cell stay safe. How the heat actually works Here’s the thing about NIR: it doesn’t behave like your standard IR heater. It uses shorter wavelengths, which means the heat doesn’t just sit on the surface or soak the whole battery like a sponge. It dives straight into the casing and the glue. It’s targeted. By tweaking the wattage and the timing, we can hit the exact temperature we need at the bond line without cooking the active chemistry inside the cell. It’s a delicate balance, but it works. Changing the physics of the line When you add a preheat stage, the whole feel of the process changes. Cold materials fight back—they resist compression. But when they’re warm? They flow. This takes a massive amount of mechanical stress off the electrodes and separators. Because the materials aren’t fighting you, you can actually dial back your press pressure. And when you lower the pressure, the risk of crushing a cell or breaching a separator pretty much disappears. The tricky parts Now, it’s not just “plug and play.” NIR is fast, but it’s picky. If your lamps are even a little too close to the battery wrap, you’ll get hot spots. That’s a nightmare because it can degrade the electrolyte. You need a really tight feedback loop—sensors that talk to the NIR output in real-time to keep the surface temperature exactly where it needs to be. And a quick tip: don’t forget the shielding. If you don’t block those emitters, you’ll find your entire machine frame heating up, which is the last thing you want.