Questions & answers

Material Densification

That depends on the cells design for an in-situ (or anode-free) lithium metal anode concept Quintus proposes a densification step of whole pouch cells. This position would fit the isostatic press after stacking and pouching.

As the high-pressure gas is working isotopically on all exposed surfaces of the treated components, the general shape of the parts does not change from the HIP process making it possible to treat any component shape if the surfaces are gas-tight.

Castings, MIM, sintered powder compacts, and AM parts are all possible to HIP, and canned powders are formed into solid components (processes called PM HIP or PM NNS (Near Net Shape)).

The largest Hot Isostatic Press (HIP) in the world has a hot zone of 2.05m diameter, 4.2m high, and is owned and operated by Metal Technology Company in Japan.

There is a great deal of interest in even larger machinery, and we have designs for >4m diameter systems for pressures >1,000 bar with temperature in excess of 1,250 °C.

In discussion with Quintus, you will be able to optimise the footprint in your facility to ensure that productivity is ensured. We help in layout discussions and can arrange the machine layout to make best use of your space. This ensures good planning of civil work, transportation and installation. We help you to get up and running so that you can increase the return on your investment.

The different capabilities of HPHTᵀᴹ are features developed for controlling the high-pressurized gas inside the pressure vessel. Having this capability enables us to steer the temperature and temperature change rate the components are subjected to, making accurate process control and heat treatments strategies possible.

HPHTᵀᴹ makes up of different features within Quintus HIP. Its capabilities are to optimize densification, heat treatment, and general processes. It’s done by controlling and steering high-pressure gas.

The upfront investment seems high, but is rather low compared to other machinery used in today’s battery manufacturing. Calculations with a realistic cost-model we established, put isostatic pressing in the lower cent area per KWh. The calculation model fits different parameters, the ones that show a high impact are pouch dimensions and vessel size, which can be adapted to customers preferences.

The batch characteristic is an important topic for discussion. Our simulation shows that automation of the loading, unloading and densification won’t be a challenge for the implementation of isostatic pressing in the overall process. Additionally, the speed of stacking/winding is limiting the process speed before densification.

We are open for different approaches, but focusing more on the pouch cell format. Concepts featuring a lithium metal anode or in situ lithium metal anode are very interesting for us on a production level of testing. We are testing solid-state electrolyte systems featuring sulfides, oxides and composites on a daily basis in our application centers in Sweden and the US.

Cold Isostatic Pressing (CIP) is a wet bag compaction method, subjecting compacted powders, enclosed by a flexible rubber mold, to extreme isostatic pressure to create optimum sintering/densification conditions. The most commonly used pressure media for CIP is water at ambient temperature.

HIP (Hot Isostatic Pressing) is a high-temperature, high-pressure process to enhance material properties. It utilizes a specialized furnace housed within a gas pressure vessel. The process typically employs argon or nitrogen gas, pressurized up to 2000 bar and heated to temperatures up to 2000°C.

The combination of pressure and temperature densifies components to near-theoretical density. It means internal defects like porosity, voids, and microcracks are eliminated.

HIP usually operates at temperatures similar to conventional heat treatment processes. So, we can integrate both procedures into a single step, called High Pressure Heat Treatment (HPHT™). This innovative approach boosts productivity while reducing the need for additional capital equipment.

HPHTᵀᴹ is short for High Pressure Heat Treatment. It includes capabilities for integrating different heat treatment strategies within the HIP process.

The main features include

  • Latest generation of temperature control and high steered cooling rates of the URC®
  • Minimum distortion gas quenching feature of the URQ®
  • Steered Cooling™
  • Quintus Purus®

The basis for these is the ability to control and steer the high-pressure gas in the vessel and furnace.

Quintus Purus is a capability developed to ensure the cleanest possible atmosphere during the HIP cycle. Its purpose is to reduce the risk of oxidation and oxygen uptake in component surfaces. It has proven vital for avoiding, e.g., alpha case on titanium alloys used in medical implants.

CIP ensures homogeneous compaction of powder-based components and is especially beneficial for components having a high diameter to length ratio such as tube or rods shaped geometries for which uniaxial pressing will create a density gradient along the length of the part.

HIP (Hot Isostatic Pressing) densifies components at high temperatures, eliminating internal defects such as pores, voids, cracks, and lack of fusion. This process enhances material properties, including fatigue strength, elongation at failure, and impact toughness, which are crucial for mission-critical applications in industries like aerospace, nuclear, and medical.

A defect-free bulk allows surface finishing techniques, such as grinding and polishing, further improving fatigue resistance, corrosion resistance, hygiene, and aesthetics.

The combination of pressure and temperature is used to maximize a powder compacts homogeneous densification by e.g., softening the polymer binder between brittle particles, or for activating additional slip systems in ductile metals, to facilitate reordering of particles for improved densification.

The production series of warm isostatic battery presses are able to deliver pressures up to 600 MPa, while reaching temperatures of 150 degree Celsius (pressure media can be water or oil).

From the two vessel technologies, mono-block and wire-wound, the wire-wound technology systems can be scaled up to a cylinder volume of 2000 L.

Uniform Rapid Cooling, URC®, is a Quintus invention which enables uniform cooling of the payload. Forced convection of high temperature and high pressure gas over a heat sink enables controllable cooling of the gas. URC® is used for metals as well as ceramic materials, to increase productivity and heat treat parts.

Uniform Rapid Quenching, URQ®, is a Quintus invention which enables high speed quenching of the payload, at similar cooling rates to gas quenching. Cold gas in the HIP is exchanged with the hot gas in the furnace at a very high rate, effectively quenching the payload in a uniform way with minimal induced stress.

Warm Isostatic Pressing, WIP, is a technology that is used for achieving maximum uniform powder compact density, using a heated, pressurized liquid media. Common pressure media include water, emulsion or oil, pressurized to 600 MPa at temperatures up to 145°C.

Modern standard HIP equipment operates up to 2000 °C and 200 MPa pressure from argon or nitrogen gas. The parameters chosen are always material-specific, keeping in mind that the elevated pressure will lower the temperature needed to achieve the same effect in a pressureless environment. This can be utilized for e.g., minimizing grain growth in sintering, avoiding part surfaces sticking, controlling microstructures, etc.

Quintus uses a standard pressure vessel rating of 200MPa gas pressure for HIP equipment up to 1.6m diameter and 600MPa for the CIP, WIP, and HPP systems using liquids as pressure media.

However, with Quintus’ innovative wire-wound pressure vessels and over 70 years of experience in designing and manufacturing them, we can offer extensive customization to meet specific customer needs, when feasible.

CIP is commonly used to ensure a homogenous powder green bodies for optimum sintering processes for metal alloys, refractory metals, brittle magnetic and ceramics, etc.

Most standard heat treatment processes for metals and ceramics, using temperature and temperature change rate, can be performed in the HIP vessel. In addition to the traditional pressureless heat treatments, the MPa pressure of the HIP process can be used both for altering the kinetics of the process and for more precise control of temperature uniformity and temperature change rates.

HIP is used to consolidate powders, solids and combinations thereof. Materials range from ceramics to metals and composite materials. Light-weight materials, high speed steels, tool steels and super alloys all use HIP, and new generations of materials such as high entropy alloys are also developed using this process.