(Reuters) – Amazon.com Inc is set to release a higher-end Kindle version with a rechargeable protective case for a better battery life, the Wall Street Journal reported on Tuesday, citing a person familiar with the matter.

The online retailer is also developing a solar-charged Kindle case, the Journal reported, citing another source.

Amazon declined to comment.

The company’s chief executive tweeted on Monday that the latest version of the reading device is ready and details could be expected next week.

(Reporting by Rishika Sadam in Bengaluru; Editing by Maju Samuel)