Outstanding Battery Anode Material Produced from Kasiya Graphite
- Kasiya graphite concentrate confirmed to be an excellent feedstock for natural graphite anode materials suitable for battery production
- Kasiya natural graphite presents a unique, low-cost opportunity to develop lithium-ion battery supply chains outside of China
- Very high quality Coated Spherical Purified Graphite (CSPG) anode material produced from Kasiya graphite concentrate has performance characteristics comparable to the highest quality natural graphite battery material produced by dominant Chinese anode manufacturers
- Electrochemical testing achieved very high first cycle efficiencies of 94.2% to 95.8% supporting long battery life
- Excellent initial discharge capacities greater than 360mAh/g as required for highest quality natural graphite anode materials.
- Very low specific surface areas (known as BET) of ≤2.0m2/g minimising the loss of lithium in the first battery charging cycle
- Excellent tap densities of 1.11 to 1.18g/cm3 meaning higher electrical storage
- Outstanding anode material results are attributed to the unique geological setting of the highly weathered Kasiya orebody compared to fresh rock hosted graphite deposits, including:
- high purity of the natural flake,
- near perfect crystallinity, and
- very low levels of sulphur and other impurities.
- Further optimisation testwork to commence using additional concentrate being generated at pilot-scale facility in South Africa
- Results will form the basis for ongoing and future discussions with potential offtakers
Managing Director Frank Eagar commented: “These results confirm that Kasiya graphite concentrate will be an excellent anode material feedstock to the battery industry. Not only is the weathered, saprolite-hosted graphite easy to purify to very high-grades, the anode material produced meets the highest industry specifications. Along with the very low BET specific surface area and high tap densities (both resulting in excellent first cycle efficiencies and initial battery discharge capacities), Kasiya has the potential to become a dominant source of graphite supply ex-China. Combining these excellent results with one of the largest graphite resources globally, industry low operating costs and lowest global warming potential, Kasiya is presenting significant advantages over its graphite peers. We look forward to further testwork and market updates as we continue to develop Kasiya as a supplier of premium quality, cost competitive natural graphite concentrate.”
ENQUIRIES
Frank Eagar (South Africa/Malawi)
Managing Director
+61(8) 9322 6322
Sam Cordin (Perth)
+61(8) 9322 6322
Sapan Ghai (London)
+44 207 478 3900
4 September 2024. Sovereign Metals Limited (ASX:SVM; AIM:SVML; OTCQX: SVMLF) (the Company or Sovereign) is very pleased to announce an update on the downstream testwork conducted at leading independent consultancy ProGraphite GmbH (ProGraphite) in Germany.
The test work program demonstrated that CSPG produced from Kasiya natural flake graphite has performance characteristics comparable to the leading Chinese natural graphite anode materials manufacturers such as BTR New Material Group (BTR).
Electrochemical testing of the CSPG samples at a leading German institute achieved first cycle efficiencies (FCE) of 94.2% to 95.8%, with results above 95% a key specification for highest quality natural graphite anode materials under the Chinese standard.
Following spheronisation and purification testwork1 which produced spherical graphite with very high purities of 99.99%, the purified spherical graphite (PSG) samples were pitch coated and carbonised to produce CSPG.
The coating process produced CSPG with very low BET specific surface area of 2.0m2/g and lower and high tap densities of 1.11-1.18g/cm3 (Table 1).
A low specific surface area is required for anode materials to minimise the loss of lithium in forming a secondary protective coating on the anode material known as the Solid Electrolyte Interphase (SEI). The pitch coating process also assists in increasing the density of the anode material as measured by the tap density – a higher density assists in storing more electrical energy in the lithium-ion battery.
Table 1: CSPG Results | ||||
|
|
CSPG Sample |
||
Sample |
Units |
1 |
2 |
3 |
D10 |
[µm] |
11.05 |
11.08 |
14.86 |
D50 |
[µm] |
17.46 |
17.27 |
23.71 |
D90 |
[µm] |
26.75 |
27.5 |
36.72 |
Tap Density |
[g/cm3] |
1.11 |
1.12 |
1.18 |
BET |
[m2/g] |
1.6 |
2.0 |
1.4 |
Electrochemical testing of the CSPG samples at a leading German institute achieved FCE of 94.2% to 95.8%, with results above 95% a key specification for highest quality natural graphite anode materials under the Chinese standard. A very high FCE minimises lithium losses in the initial formation cycles of a lithium-ion battery, supporting battery life. Kasiya CSPG also met the criteria for an initial discharge capacity of more than 360mAh/g (ampere-hours per gram) for highest quality anode materials, with initial capacities of 362-366mAh/g. These results will be used to fast-track discussions with potential offtakers.
Table 2: Electrochemical Results – China CSPG Standard |
|
|||||||||||||
|
CSPG Sample |
China Standard GB/T-24533-2019
|
||||||||||||
1 |
2 |
3 |
Grade I |
Grade II |
Grade III |
|||||||||
First Cycle Efficiency |
[%] |
95.8 |
94.2 |
95.8 |
≥95 |
≥93 |
≥91 |
|||||||
Initial Capacity |
[mAh/g] |
362 |
364 |
366 |
≥360 |
≥360 |
≥345 |
|||||||
Furthermore, the testwork demonstrated that CSPG produced from Kasiya natural flake graphite has initial performance characteristics comparable to the leading Chinese natural graphite anode materials manufacturers such as BTR. BTR has a 20-year track record in the production of lithium-ion battery anode materials, is a dominant player in the market and has recently concluded anode material offtake agreements with global automotive companies including Ford. BTR’s highest specification CSPG materials, that have low swelling, long cycle life, good processability and outstanding electrochemical performance include their GSN17 and LSG17 products (with D50 of 17.0+/- 1.5μm).
Table 3: Electrochemical Results – BTR CSPG products |
|
|||||||||
|
CSPG Sample |
BTR3
|
||||||||
1 |
2 |
GSN 17 |
LSG 17 |
|||||||
First Cycle Efficiency |
[%] |
95.8 |
94.2 |
≥95 |
≥94 |
|||||
Initial Capacity |
[mAh/g] |
362 |
364 |
≥360 |
≥355 |
|||||
D50 |
[μm] |
17.5 |
17.3 |
17.0+/- 1.5 |
17.0+/- 1.5 |
|||||
In December 2023, China imposed trade restrictions on graphite that required producers to apply to the government for permits to export high-grade graphite materials and related products. Given China’s dominance of natural graphite and graphite derived products such as CSPG, global EV production and Net Zero ambitions could be negatively impacted given the lack of anode industry development ex-China. In May 2024, the US government imposed a new 25% tariff on natural graphite from China, as part of a broader initiative that included an increase of tariffs on EVs and lithium-ion batteries.
High performance CSPG materials manufactured from Kasiya natural graphite present an opportunity for development of ex-China supply chains for battery anode materials. Sovereign believes that the outstanding electrochemical results for Kasiya CSPG are as a result of the unique geological setting of the Kasiya orebody. The near perfect crystallinity i.e. fully ordered graphite resulting from the very high metamorphic grade of the underlying host rock (paragneiss metamorphosed to granulite facies) and the high purity of the natural flake being assisted by the highly weathered nature of the ore.2 This is as opposed to fresh rock hosted graphite deposits which generally have much higher impurity levels including sulphur, which negatively impacts electrochemical performance. The very low sulphur profile of Kasiya graphite is due to the fact that the primary sulphide minerals have been altered to sulphates by the intense weathering. The sulphates are water soluble and are leached from the ore during weathering.
Further optimisation testwork for anode materials is planned, using additional graphite concentrate currently being generated at pilot-scale in South Africa. This material will also be used to provide offtaker evaluation samples.
A program for assessing Kasiya concentrate for traditional refractories and foundry applications has also been developed. The coarse component of the pilot plant concentrate will be used for this testwork program.
1 Refer to ASX Announcement “Downstream Testwork Demonstrates High Quality Graphite” dated 15 May 2024
2 Refer to ASX Announcement “Kasiya Graphite Shows Excellent Suitability For Use In Lithium Ion Batteries” dated 8 June 2023
3 BTR anode material specs taken from this webpage: https://www.btrchina.com/en/NegativeProducts/info.aspx?itemid=1069
Competent Person Statement
The information in this report that relates to Lithium-Ion Battery Testwork is based on information compiled by Dr Surinder Ghag, PhD., B. Eng, MBA, M.Sc., who is a Member of the Australasian Institute of Mining and Metallurgy (MAusIMM). Dr Ghag is engaged as a consultant by Sovereign Metals Limited. Dr Ghag has sufficient experience, which is relevant to the style of mineralisation and type of deposit under consideration and to the activity which he is undertaking, to qualify as a Competent Person as defined in the 2012 Edition of the 'Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves'. Dr Ghag consents to the inclusion in the report of the matters based on his information in the form and context in which it appears.
The information in this report that relates to Exploration Results (table 1) is based on information compiled by Mr Samuel Moyle, a Competent Person who is a member of The Australasian Institute of Mining and Metallurgy (AusIMM). Mr Moyle is the Exploration Manager of Sovereign Metals Limited and a holder of ordinary shares and unlisted performance rights in Sovereign Metals Limited. Mr Moyle has sufficient experience that is relevant to the style of mineralisation and type of deposit under consideration and to the activity being undertaken, to qualify as a Competent Person as defined in the 2012 Edition of the 'Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves'. Mr Moyle consents to the inclusion in the report of the matters based on his information in the form and context in which it appears.
Forward Looking Statement
This release may include forward-looking statements, which may be identified by words such as "expects", "anticipates", "believes", "projects", "plans", and similar expressions. These forward-looking statements are based on Sovereign’s expectations and beliefs concerning future events. Forward looking statements are necessarily subject to risks, uncertainties and other factors, many of which are outside the control of Sovereign, which could cause actual results to differ materially from such statements. There can be no assurance that forward-looking statements will prove to be correct. Sovereign makes no undertaking to subsequently update or revise the forward-looking statements made in this release, to reflect the circumstances or events after the date of that release.
This announcement has been approved and authorised for release by the Company’s Managing Director CEO, Frank Eagar.