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 atmosphere acts in an isotropic manner on the surfaces of components in the hot zone, the mechanical force exerted is even. This means that solid parts do not change shape in the HIP. The gas presses on internal channels in the same way as long as they are open to the gas. Casting, MIM and AM parts are all possible to HIP, and canned powders can be formed into solid components (PM HIP or PM NNS, Powder Metallurgy Near Net Shape).

The largest press 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 for even larger machinery.

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.

HPHTᵀᴹ utilises convection of the HIP pressure medium over cold surfaces inside the HIP vessel. These cold surfaces are made possible through cooling due to the design of the Quintus equipment. The flow of gas can be controlled and directed allowing you to steer cooling at a specific rate. Quintus URC® and URQ® technologies are key in making this possible.

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) entails subjecting components or powder in moulds to extreme isostatic pressure, up to 600 MPa (87,022psi) and at ambient temperature. Common pressure media include water, emulsion or oil and in some cases components my be bagged.

HIP uses a furnace inside a pressure vessel. Very high pressure gas, usually argon at elevated temperature, is used to consolidate material and remove internal defects such as porosity and microcracks. As HIP uses temperatures very close to those used for heat treatment, creep and diffusion occur, along with mechanical deformation of defects due to extreme external pressure.

High Pressure Heat Treatment (HPHTᵀᴹ) is the term used by Quintus for heat treatment in combination with steered heating and HIP processing. The steered cooling capability in Quintus equipment allows heat treatment directly after the densification steps.

Quintus has developed routines to ensure a clean atmosphere during the HIP cycle, leading to lower risk of oxidation during processing compared with traditional methods. This technology is new, and will revolutionise clean processing inside the HIP.

Powder subjected to extreme pressure in a mould is compacted into a solid, with a density of up to 95% depending on the material.

As HIP removes internal defects in the load, material properties such as fatigue life, elongation and impact toughness are improved. Subsequent grinding of polishing of surfaces demonstrates excellent roughness values and no unwanted porosity is uncovered by these operations. The HIP has already fixed those.

When powder is subjected to high pressure in a mold, it can be compacted into a solid with a density of up to 95%, depending on the material used.

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) entails subjecting components or powder in moulds to extreme isostatic pressure, up to 600 MPa (87,022psi) and at ambient temperature. Common pressure media include water, emulsion or oil and in some cases components my be bagged.

Modern HIP equipment from Quintus operates up to 2000⁰C (3632⁰F) and 200MPa (30,000 psi). The parameters chosen are material specific, and often an increased pressure can allow lower temperatures to be use, preserving the material microstructure. Of course the HIP cycle used should not exceed the melting temperature of the material to be treated.

The standard range of equipment, up to 1.6m diameter is rated to 200MPa as standard. The larger the diameter of the hot zone, the more force is exerted on the end closures. The Quintus wire-wound frame design is made to handle this, and the pressure rating of larger equipment can be discussed based on your needs.

Metals, soft magnetics and ceramic powders are typical materials. In some cases CIPed material may be further processed using Hot Isostatic Pressing.

All manner of materials can be heat treated with solutionizing steps in the HIP. Aging can also be performed on hardenable alloys to bring strength up with pore-free microstructures. Ceramic materials such as silicon nitride can also benefit from much higher cooling rates than previously possible. Both of these are helped by the pressure inside the vessel.

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.