FOCUS ON STAMPING
Schuler supplies the production line as a turnkey solution including tools , integrated control unit and full service .
MAKING AN IMPACT
Schuler outlines how impact extrusion can be used to efficiently manufacture prismatic battery cell cases and lids for electric vehicles .
“ With impact extrusion , up to five times more parts can be made than with deep drawing , while the material utilisation is also much higher .”
With impact extrusion , up to five times more battery cells per minute can be made than with deep drawing .
Introduced in the early 1990s , the prismatic cell satisfies the demand for thinner sizes and lower manufacturing costs . Wrapped in elegant packages resembling a box of chewing gum or a small chocolate bar , prismatic cells make optimal use of space by using the layered approach . These cells are predominantly found in mobile phones with lithium-ion . Each manufacturer designs its own .
Prismatic cells are also making critical inroads into larger formats . Packaged in welded aluminium housings , the cells deliver capacities of 20 to 30Ah and are primarily used for electric powertrains in hybrid and electric vehicles . The prismatic cell requires a slightly thicker wall size to compensate for the decreased mechanical stability from the cylindrical design , resulting in a small capacity drop . Optimising the use of space makes up this loss . Prismatic cells for portable devices range from 400mAh to 2,000mAh .
Prismatic cells are contained in a rectangular can . The electrodes are either stacked or in the form of a flattened spiral . They are usually designed to have a very thin profile for use in small electronic devices such as mobile phones .
Prismatic battery can production
Schuler is known for supplying systems forming structural and body parts made of high-strength steel , aluminium and composites . This lightweight technology is also used for electric vehicles . However , Schuler also offers equipment for the manufacture of electric motors ’ cores ; the laminations . The battery cases at the heart of the electric vehicle can also be produced with Schuler solutions .
“ Generally speaking , there are two ways to make prismatic battery cans ,” Schuler ’ s Markus Röver explained at a virtual battery exhibition held by the German Mechanical Engineering Industry Association ( VDMA ) last year . “ Either you start with a coil of sheet metal and stamp a blank out of it to form the cell case by deep drawing , or you start with a piece of aluminium called slug .”
Yet , in the first case , fabricators can only exploit part of the metal strip depending upon the
Markus Röver , Head of Sales size of the blank and the
E-Mobility , Schuler . coil width .
“ Here , you can achieve utilisation of 65 per cent , which means that 35 per cent of your metal goes back to scrap ,” explained Röver , who is head of sales e-mobility at Schuler . “ You also have to complete quite a few complex production
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