Ballard Power Sys (BLDP) gains 1.97% Posted on May 31, 2021 By News Team Ballard Power Sys (NASDAQ: BLDP) shares gained 1.97% to end trading Thursday at $17.12 per share – a net change of $0.33. Shares traded between $17.22 and $16.39 throughout the day. 4456185 shares of Ballard Power Sys exchanged hands.