Five Smart Ways To Improve EV Battery Production

Batteries and battery management systems are the heart of today’s electric vehicles. These components define the performance, safety, and driving range of more than 16.5 million¹ electric vehicles currently on the road.

As electric vehicle and battery manufacturers continue to look for ways to increase the efficiency and speed of their production processes, many turn to Nordson EFD for precision fluid dispensing solutions. EFD jet valves, dispense valves, and automated dispensing systems help manufacturers produce high-performance, defect-free batteries at faster production speeds by applying precise amounts of fluid within tight deposit size and positional tolerances.

With the transportation market pivoting to an electrically powered transportation paradigm, smart manufacturers are focusing on improving the quality and throughput of their EV production process. To meet ambitious production goals, organizations must adopt efficient manufacturing techniques to succeed.

Mastering automated fluid dispensing for battery cell manufacturing and EV battery assembly is a proven way to obtain manufacturing efficiencies and build high quality battery packs. But understanding that adept fluid dispensing offers manufacturing advantages and determining where to focus your EV battery manufacturing attention can be challenging. Smart manufacturers impact their EV battery production process by concentrating on these five areas of fabrication:

1. For cell manufacturing, precisely align key components to improve overall performance and lifetime of the battery.
2. For cell manufacturing, ensure precise electrolyte filling for the overall performance and stability of the cell.
3. For module and pack assembly, use a controlled and automated thermal interface material (TIM) dispensing method to prevent thermal runaway, which is critical for overall battery pack safety.
4. For module and pack assembly, reduce the cycle time and increase the repeatability and accuracy of the bonding operation of the battery cells to the battery tray to increase production yield and save valuable production time.
5. In all areas of fabrication, future proof by staying flexible in production methods by adapting to new battery chemistries and technologies.

1. For cell manufacturing, precisely align key components to improve overall performance and lifetime of the battery

The precise positioning and quantity of adhesive during the battery manufacturing process has a strong impact on the battery’s functionality, quality, and longevity over its lifespan.

For battery technology to operate as intended, precise alignment between the cathode, anode, and separator must be maintained. Fluid dispensing expertise from Nordson EFD is essential for recommending the correct solution for the exact, repeatable application of adhesive to facilitate accuracy in battery layer alignment within the cell. Focusing on the precise glue dispensing step is where manufacturers can efficiently meet safety goals (preventing battery shorts), while imparting build quality into the battery and saving on scrap.

For this task, the PICO Pµlse XP jetting system offers many advantages for battery manufacturing because it enables manufacturers to accurately, repeatedly, and precisely dispense fluids. Offering micron (µm) level stroke adjustment (a human hair is approximately 70 microns), the solution can repeatedly dispense fluids over long periods of time, regardless of environmental factors. In addition, the system can apply micro-deposits as small as 0.5 nL at speeds up to 1000Hz (deposits per second) continuously.

The Nordson EFD PICO Pµlse XP jetting system offers many advantages for EV battery manufacturers including improved accuracy, repeatability, and precision in fluid dispensing.

2. For cell manufacturing, ensure precise electrolyte filling for the overall performance and stability of the cell

Precise electrolyte filling is important for battery manufacturers because using just enough electrolyte to wet the components contributes to optimal cell performance. Electrolytes are known to be aggressive fluids, so careful handling of the material is essential for satisfactory results. Smart manufacturers pay particular attention to their choice of valves for this process, as they must be able to stand up to the aggressive nature of the electrolyte without requiring frequent valve change outs.

Using efficient manufacturing practices is important for meeting production goals and increasing production yields, particularly for lithium-ion cell fabrication for electric vehicle batteries.

For this application, Nordson recommends that manufacturers use a 702 series mini-diaphragm valve. This valve is particularly well suited to filling electrolyte chambers because it provides a drip-free dispensing. The mini-diaphragm valves feature a distinctive design that eliminates trapped air bubbles and offers quick, clean cutoff. The 702 mini-diaphragm valves offer a tamper-resist stroke adjustment, consistent shot-to-shot performance, and faster throughput. In addition, the 702 Series valves enable users to mount more valves per fixture plate and dispense fluids in tighter spaces, allowing greater throughput and productivity.

The 702 series mini diaphragm valve is ideal for electrolyte filling because the valve can stand up to the aggressive nature of the electrolyte without requiring frequent valve change outs.

3. For module and pack assembly, use a controlled and automated thermal interface material (TIM) dispensing method to prevent thermal runaway, which is critical for overall battery pack safety

Thermal runaway is a chain reaction within a battery cell that involves a rapid rise in the temperature of the battery. It occurs when the temperature inside a battery reaches a point that causes a chemical reaction to occur inside the battery. This chemical reaction produces more heat, driving the temperature higher — causing further chemical reactions that create more heat.

Thermal runaway is a significant threat to the safety of a battery pack, and to the Electric Vehicle in operation. One method to prevent thermal runaways is the use of thermal interface materials (TIM), since the material absorbs the heat from the overheated batteries.

Causes for thermal runaway include:

• An internal short circuit caused by physical damage to the battery or poor battery maintenance.
• Overcharging a battery beyond its safe max voltage (to extend the distance an electric car will run, for example), which can permanently damage the battery and lead to thermal runaway.
• Rapid charging because rapid charging can lead to excessive currents.
• Finally, temperatures outside of the safe region on either the low or high side degrades a battery’s performance. This leads to irreversible damage to the battery and possible triggering of the reaction.

Thermal runaway is a significant threat to the safety of a battery pack, and to the electric vehicle in operation. One method to prevent thermal runaways is the use of thermal interface materials (TIM), since the material absorbs the heat from the overheated batteries. To achieve this, design engineers need to calculate and precisely apply the right amount of the selected TIM chemistry at the exact locations in the battery module and the battery pack. This is an operation where the use of fluid dispensing technology can prevent thermal runaway.

Using a 797PCP-2K progressive cavity pump to automate the TIM dispensing benefits manufacturers with a precise, repeatable process.

Nordson EFD technology helps automate TIM dispensing using the fluid dispensing capabilities of 797PCP-2K progressive cavity pumps. The quality assurance this manufacturing technology imparts is precise dispensing of the right amount of fluid in a repeatable manner — which is of particular importance with TIM dispensing.

4. For module and pack assembly, reduce the cycle time and increase the repeatability and accuracy of the bonding operation of the battery cells to the battery tray to increase production yield and save valuable production time

Using efficient manufacturing practices is important for meeting production goals and increasing production yield. How you bond the battery cells to the battery tray can provide measurable production efficiencies. For cell/tray bonding, manufacturers can leverage the speed and accuracy that non-contact dispensing affords, such as reduced waste, fewer rejects, and improved throughput.

For cell / tray bonding, manufacturers can leverage the speed and accuracy that non-contact dispensing affords – including reduced waste, fewer rejects, and improved throughput.

A non-contact dispensing solution like Nordson EFD’s PICO Pµlse jet valve can be the difference between repeatable battery cells to battery tray bonding, and struggling with frustrating production errors. Using the PICO Pµlse solution’s exchangeable, modular jet valve technology, manufacturers can apply precise, repeatable micro-deposits at 1000Hz continuously, with bursts up to 1500Hz.

Repeatably dispensing adhesives with the PICO Pµlse offers a value to EV battery producers because it enables them to use just the right amount of fluid to bond to the tray without any overflow. In addition, organizations can reduce material costs because precise fluid dispensing uses the right amount of adhesive for the task.

Not only do organizations find that they can optimize battery cell bonding to the battery tray, but they can also reduce cycle times, too. Difficult to reach dispensing areas like the complex honeycomb structures found in many battery modules can present a challenge for bonding and dispensing, but jet valves paired with the right automated dispensing system provide the flexibility to apply fluids and adhesives onto nearly any battery tray geometry.

5. In all areas of fabrication, future proof by staying flexible in production methods by adapting to new battery chemistries and technologies

Currently, Li-ion batteries are the prevailing power technology for EV vehicles. But the dynamic nature of market forces and disruptive technology is such that savvy battery builders are keeping their eye on emerging battery chemistries. These include solid state battery and fuel cell designs.

Solutions for each phase of EV battery fabrication: Fluid dispensing technologies help future proof manufacturers as new battery chemistries develop.

Manufacturers using Nordson EFD fluid dispensing technologies are in a strong position as prevailing battery technologies evolve to any of these configurations, since our dispensing solutions are used to manufacture various types of cell geometry. In addition, Nordson EFD and the Nordson family of companies are actively engaged in researching the next generation of battery innovations like different cell chemistries and technologies.

While the battery technology may evolve, your fluid dispensing technology investment is poised to move with changes in your manufacturing process, since it has the flexibility to build different cell chemistries, geometries, and technologies.

Conclusion

As the world embraces EV batteries as the power source of the future, intelligent manufacturers are wise to analyze the systems they are using to build batteries for tomorrow’s transportation needs. Smart manufacturers understand that focusing on these five tasks offer a strong return on investment in a rapidly changing manufacturing landscape:

1. For cell manufacturing, precisely align key components to improve overall performance and lifetime of the battery.
2. For cell manufacturing, ensure precise electrolyte filling for the overall performance and stability of the cell.
3. For module and pack assembly, use a controlled and automated thermal interface material (TIM) dispensing method to prevent thermal runaway — which is critical for overall battery pack safety.
4. For module and pack assembly, reduce the cycle time and increase the repeatability and accuracy of the bonding operation of the battery cells to the battery tray to increase production yield and save valuable production time.
5. In all areas of fabrication, future proof by staying flexible in production methods by adapting to new battery chemistries and technologies.

By focusing on these areas of your production process, your organization will manufacture high performance batteries with a long-life cycle while maximizing production yield. In addition, your company will have the flexibility and technical competency to master change as the electric powered revolution unfolds.

As always, an experienced fluid dispensing application specialist can help you find the best possible dispensing solution for your EV battery application.

Resources

• Applications for the Electric Vehicle (EV) Industry
• Nordson Battery Cell Manufacturing Capabilities

Reference

[1] Paoli, Leonardo. Electric Vehicles – Analysis – IEA. International Energy Agency (IEA). IEA Electric Vehicles, Technology Deep Dive. Tracking Report – September 2022.