The ShFE said on May 8 it would accept delivery of briquettes against its nickel futures contract in response to growing demand from the electric vehicle (EV) sector in China, with the change to be implemented on Oct. 16.

But no list of deliverable brands has yet been published.

"There are still no nickel briquettes among the deliverable brands. The relevant access and delivery management rules are still being designed and studied," the ShFE said in a statement.

The ShFE previously only allowed delivery of plate-shaped nickel cathodes, although briquettes, which can be dissolved into battery chemical nickel sulphate, are deliverable on the London Metal Exchange.

The ShFE needs consent from producers to list their brands and decide whether to set premiums or discounts to the Shanghai nickel price, CRU analyst Ellie Wang said.

Once brands are registered, traders are likely to choose briquettes for ShFE delivery as they usually carry a lower premium than cathodes, which could push Shanghai nickel prices down, Wang added.

An official from ShFE's commodity department, who asked not to be identified, said at an industry conference on Thursday that Oct. 16 only reflected when briquettes could be delivered in principle and that work on details was in progress.

The official declined to say when they could be delivered.

Producers of briquettes include Glencore, BHP, Russia's Norilsk Nickel and South Africa's Impala Platinum Holdings.

Impala, which previously said listing its briquettes on the ShFE was not a priority, had no immediate comment on Thursday. Glencore declined to comment, while Nornickel and BHP did not immediately respond to requests for comment.

(Reporting by Min Zhang and Tom Daly; Editing by Barbara Lewis and Alexander Smith)