Instruct: Classify Amazon reviews into positive or negative sentiment
Query: On first use, plastic connecting to battery grew extremely hot with acrid smell...almost fire.

Plugged in and noted red light on the charging unit. Looks good. Within ~10 minutes, noticed an acrid smell of overheating electronics. Touched battery charger where the LED "charging light" is...and it was extremely hot. Smell was clearly coming from the charger.Given this was the first time I used the charger...and it almost called a fire, I would say "stay away." Returning defective unit and hoping I get a refund.