Ash's Pikachu

Ash's Pikachu is the very first Pokemon that Ash Ketchum ever recieved and since then has became his main partner since the beginning of his journey as a Pokemon Trainer.

History
Pikachu was Ash's Starter Pokemon that was chosen by him due to being late to obtain the other three Starter Pokemon (who were also taken by trainers). At first, Pikachu didn't get along with Ash until he saved him from a flock of Spearow and became good friends. Throughout his entire journey, Ash had used his Pikachu in many Gym, League, and Frontier battles, allowing Pikachu to come with him toward many new adventures and winning battles. Pikachu has learned powerful attacks, including its newly-learned Electro Ball.

In Unova
Ash decided to just bring Pikachu to Unova with him, just like he did in Hoenn and in Sinnoh. In The Shadow of Zekrom!, Pikachu encountered Zekrom which unaware by Ash, caused Pikachu to lose its ability to use Electric-type moves. Ash finally noticed this when it battled Trip's Snivy, losing in the process. In Enter Iris and Axew!, it regained its ability to use Electric-type attacks and was used in battle which led to the capture of Pidove. In A Sandile Gusher of Power!, he made rivals with a wild Sandile wearing shades when looking for Oshawott at a spa near Route 1.

In The Battle Club and Tepig's Choice!, Pikachu's next battle was against a trainer's Dewott at the Battle Club that Ash and Iris visited in Accumula Town. The Dewott was speedy and dodged Pikachu's Thunderbolt right before it hit back with Razor Shell. The battle was postponed due to Team Rocket entering the place as well.

In Triple Leaders, Team Threats!, Ash used Pikachu in his Gym battle at the Striaton Gym where he faced Cress and his Panpour Even though he tried his best, Pikachu was just not as fast as Panpour and was defeated without landing a single hit.

In A Battle for Club Champ!, he battled Trip's Tranquill, who had already taken out Ash's Oshawott and Tepig. It took a beating from multiple Aerial Aces, but showed Trip the power of its electrical attacks by defeating Tranquill with Volt Tackle. It then battled Snivy again, who by then had evolved into Servine. However, despite not being incapacitated, he was once again defeated.

In Minccino-Neat and Tidy!, Ash used Pikachu in a battle against Bianca and her Pignite. Even though he had some trouble at first, Pikachu was able to pull through in the end and defeat Pignite with a powerful Volt Tackle.

Volt Tackle was Pikachu's main signature move until 253 episodes later during the events of Dancing With The Ducklett Trio!, Ash's hat was stolen by a group of troublesome Ducklett with powerful Scald attacks. After an umbrella closing Pikachu when he used his Thunderbolt prevented his Electric attacks again. Ash noticed this when he ordered a Thunderbolt. After being thrown back again, Pikachu learns Electro Ball and sends the Ducklett Trio into the air. He used this attack to deflect the Sunglasses Krokorok's Stone Edge and hit it instead, knocking Krokorok into the air.

Pikachu was used in Ash's third Gym battle in ''Battling for the Love of Bug-Types! ''against Burgh's Leavanny. He was wrapped up by Leavanny's string shot and was unable to break free. He then spins around and breaks free from the web and dodges a String Shot followed by Thunderbolt to cancel it out. He then used a combination of Iron Tail and Electro Ball to defeat Burgh's Leavanny and won Ash's covenant Insect Badge.

In Club Battle Finale:A Heroe's Outcome!, he was used by Ash in the final round of the Nimbasa Town Club Battle tournament where he was up against Iris and her Excadrill. Pikachu had hard time battling Excadrill due to his Electric-type attacks doing absolutely no effect on it. Pikachu surprisingly battled, but fainted first, and Iris won the tournament.

In BW050, he was used in Ash's Gym battle with Nimbasa Gym Leader Elesa, despite Ash claiming that he rather use his other Pokemon than him. After he couldn't choose who to go in Palpitoad and Snivy's place, Pikachu angrily zapped him, and was up against Emolga. Despite Emolga knowing Electro Ball as well, he easily defeats it with Quick Attack. Later, he battles her Tynamo who had a powerful Tackle. He easily defeats it with a single Iron Tail and wins the Gym battle.

Pikachu's Attacks

 * Thundershock
 * Thunderbolt
 * Agility
 * Quick Attack
 * Thunder
 * Double-Edge
 * Tackle
 * Leer
 * Iron Tail
 * Volt Tackle
 * Electro Ball
 * Electro Web

In Japan

 * Ikue Ohtani

In Dub

 * Rachel Lillis

Trivia

 * Pikachu is the only Pokemon Ash had brought with him to every region he enters.
 * Pikachu is Ash's only Electric-type Pokemon.