The USS Electrode NCC-909 and it's sister ships (NCC-910 USS Anode & NCC 911 USS Cathode) were the last starships built under Starfleet's Warp 6 starship project before the warp 7 starship project began in the 2230's.
Originally 12 ships were proposed for the class, but with Warp 7 starship designs on the drawing boards, Starfleet Procurement cancelled the project after only 3 ships had been built, in 2230.
Capable of Warp 6.1 cruising and a maximum velocity of Warp 6.9, the Electrode Class were the fastest of the Warp 6 starships in Starfleet. A SB24 Warp nacelle refit, in 2236, increased this to Warp 6.4 cruising & Warp 7 maximum speed.
The class was completely withdrawn & scrapped, in 2269, after serious microfractures were discovered in the Warp Core of NCC-911 USS Cathode. This raised immediate safety concerns for the whole class. By this time, they were already obstelete, being assigned to cadet shuttle take-off & landing training duties for many years.