I know this is an old thread....The question still remains will the OLED battery FIT in a LCD steam Deck.
According to some YouTubers, it does fit, the cover does close and it did power up. Yet, I can't find anyone who actually did this upgrade.
I posted this question on Reddit to try to find if anyone has tried this...
[link|https://www.reddit.com/r/SteamDeckModded/comments/1hf3tdz/oled_50w_battery_into_an_lcd_steam_deck_anyone/|OLED 50w battery into an LCD steam deck, anyone actually attempt it? : r/SteamDeckModded|new_window=true]