May 11, 2023
To real fight climate change with e-mobility, we need to consider the entire value chain of e-vehicles, from design to second life. Car and battery weight, performance, range, serviceability, and recyclability – the foundation for consuming fewer resources over the entire life cycle of the electric vehicle is laid in the design phase. What is often underestimated is the impact of material and energy consumption during production on the overall carbon footprint of e-mobility.
Our strong aim is to support our customers in reaching their environmental targets and KPIs in the manufacturing process. There are many levers that directly or indirectly influence the CO2 footprint of production and of the battery in a subsequent operation. Here are eight things you can do to improve the carbon footprint of your battery production line.
1. Decide on energy-optimized joining technologies
The decision on the joining technology is made at the design stage. In addition to the joint properties and benefits, consider the energy efficiency of the respective joining technology itself. Self-pierce riveting (SPR) for example is a cold and clean joining technology, which is suitable for battery module and tray assembly.
Our Henrob SPR systems require low running power and air supply per se. Their energy recovery capacitor lower CO2 emissions by capturing energy from braking in the joining cycle to set the next rivet, similar to how hybrid cars work. By reducing energy input from 0.85 Wh (standard system) to 0.68 Wh per rivet, CO2 emissions are cut by 19 % (2.25 tons per year) for 150,000 battery carrier modules.
2. Go for multi-X solutions if possible
Modern EV batteries, like cylindrical cells in honeycomb structures, have more cells, requiring multiple dispensing tasks at short cycle times such as thermally conductive cell bonding. Scalable equipment can be a great advantage. Our Scheugenpflug multi-nozzle dispenser for example integrates multiple metering units into one system with a common servo motor for all units. This saves space and reduces the CO2 footprint of your production line.
For tightening the battery modules into the tray, multi-spindle solutions are available. With synchronized tightening programs, they ensure precise assembly even with complicated conditions like the soft joint behavior of gap filler under the modules. All needed components are directly available on the robot. That saves floor space, reduces the number of robots and controllers, and can reduce cable lengths by up to 90 %.
3. Save on compressed air
Compressed air is one of the huge CO2 and cost drivers in factories. The industry sector is still a long way from compressed air-free production, but there are more and more starting points.
For our K-Flow flow drill fastening systems – suitable for example for battery tray assembly or cover joining with single-sided access – we have developed an alternative to screw blow feeding. Our HLX 70 magazine sits directly on the joining tool head and can hold up to 70 fasteners. The system requires 64 % less compressed air compared to blow feed system. This saves energy for compressed air generation and the associated CO2.
4. Invest in high precision applications
Battery production involves various dispensing processes such as cell bonding, gap filler applications, and battery sealing. In many cases, too much material tends to be applied to play it safe and ensure function. True to the motto, as little as possible, as much as necessary, however, precise application technology can save considerable amounts of material.
At the same time, more precision means less manual rework, fewer rejects, and less material waste that needs to be disposed of – adding up to CO2 savings along the process. One example is corrosion protection with the application of wax to the corrosion-prone joints and trims edges on the outer skin of the battery.
With our IDDA.Seal technology, we can apply the material with pinpoint accuracy in a 3D print-like manner. Compared to common flat or jet stream technology, IDDA saves up to 40 % of the material and extends the lifetime of the battery thanks to long-term corrosion protection.
5. Measure, calculate, adjust
Especially in gap filler applications, large volumes of thermal interface materials (TIM) are applied to the battery tray. Usually, too much of this costly and heavy material is applied Increasing weight that impairs EV range and costs.
With Smart.Adjust, we have developed a solution that exactly measures the required material volume. Based on a 3D scan of the battery tray surface and the module bottom side, the Volume.Adjuster software calculates the exact volume, and the application system adjusts the parameters accordingly. This saves up to 20 % thermal interface material and up to 2 kg weight per battery, resulting in an improved overall CO2 footprint and battery range.
6. Do not accept material supply waste
In dispensing systems, the materials mostly need to be fed from barrels. It is common that material supply units cannot empty the barrels completely. A residue always remains in the barrel and must be disposed of. In addition, the barrel change involves several liters of venting discard.
The Plus.Supply significantly reduces waste. A particular combination of a vacuum pump with a flat follower plate increases the material yield from the barrel and reduces venting discard. While standard pumps have a material yield of approx. 95,9 % according to internal calculations, the Plus.Supply manages to achieve 99,4 % usable material per barrel. These material savings, less material waste, and less disposal efforts can add up to 65 tons of CO₂ savings per system per year (calculated for exemplary gap filler application in EV battery assembly).
7. Inspect the adhesive bead
When it comes to bead inspection, the focus is primarily on quality, but there are sustainability aspects as well. With our tailored solutions you detect errors in bead width, position, volume, and continuity.
Processes like cell bonding, cover sealing or other bonding and sealing applications within the battery can be safeguarded. With immediate feedback on the adhesive application, the operators can identify the source of any defects or quality issues at an early stage in production and can take countermeasures.
This improves process efficiency and reduces scrap and material waste. Increased precision achieved via interaction of exact dispensing technology and bead inspection even allows for smaller bead diameters and volumes, resulting in material and CO2 savings.
8. Keep an eye on the efficiency of your dispensing system
Checking adhesive dispensing system parameters constantly is crucial. Even slight changes in the settings can reduce material and energy consumption, wear-out, as well as improving component lifetime. Some factors worth examining include:
- Barrel leftovers: By adjusting the parameters and with smart retrofits, material waste from barrel leftovers can be reduced.
- Purge volume pump: Minimize purging volume during pump ventilation means material savings during barrel changes.
- Purge volume meter: Optimize 1K / 2K purging volumes during production breaks for material savings with consistent application quality.
- Air consumption pump: Adjustment of pump pressure to minimize air consumption and wear-out.
- Setpoint barrel heating: Adaption to production requirements to avoid energy loss due to long pre-heating.
With our application efficiency check, we help you to optimize the performance of your system. Our checks have proven, that our customers save up to 13 tons of CO2 per system per year (estimation based on average CO2 values) and up to 27 % of the costs with the optimizations mentioned above.