Battery problem when playing on wifi.

I was trading over wifi on my pokemon diamond and all of a sudden my ds battery light went red and it was fully charged too. So I saved and turned off my ds and then turned it back on and the light was green again and I continued to play on my ds. The light didnt turn red at all during that time. Is there something wrong with my ds battery or my ds?

WiFi connections and any exchanges over said network will use a lot more battery power than standard, stand-alone gaming. Your system didn't have enough jazz to stay online and actively swap info, but offline play takes less so the battery had enough to play. Simple as that. If you aren't experiencing any other drops in power, mystery solved

Next Caller.

Wifi Uses a lot more battery power but It shouldn't have gone red straight after a full charge

Maybe you didn't charge it properly?