Actually, the Switch needs be charged every few hours, I didn't use my 3DS for weeks after charging it to 100%. after the weeks i powered it back on and it was still at 86%!
3DS BATTERY; SWITCH BATTERY; OH, YOU HAVEN'T USED ME IN 2 YEARS? IT'S COOL, WE'RE AT 86%. LET'S PLAY SOME DDD AND WATCH RIKU AND MICKEY BE AMBIGUOUSLY GAY FOR SORA. NEEDS TO BE CHARGED EVERY FEW MONTHS TO STAY HEALTHY; DRAINS RAPIDLY WHILE OFF. PROBABLY FRAMED JARED FROM SUBWAY