An investor at Maxwell Technologies Inc. on Monday lodged the latest challenge to Tesla’s planned $218 million acquisition of the small manufacturer of energy-storage products, saying that the Maxwell board had failed to disclose information regarding potential conflicts by the firm’s financial adviser.

The class-action complaint, filed by Maxwell investor Davis Rodden, targeted the company’s board and sought additional discloses about Barclays Capital Inc.’s current and prior engagements outside of the all-stock deal, which was announced last month.