YORK COUNTY, Pa -- Lithium ion batteries are what power your cellphones and laptops, but recent reports of those batteries exploding or smoking have led to the recalls of millions of products.
Like the Samsung Galaxy Note 7 and various brands of hoverboards.
FOX43 finds out what is causing these batteries to overheat.
"There are about 5 or 6 different varities of lithium ion batteries today," said professor Wayne Blanding, the head of the York College electrical engineering program
Experts say the lithium ion battery is one of the best and more affordable batteries on the market.
Blanding says the battery is flammable though and metal plates inside are under pressure.
"If those metal plates short together even if the battery is in your pocket or purse or in your luggage, potentially under that manufacturer defect, it could just suddenly cause that short circuit, that overheating effect and the fire."
Recently, Samsung spent a lot of money to fix a battery issue.
The company's Galaxy Note 7 had to be recalled because of what was called low-quality battery cells.
That basically means there's a chance the battery could fail or overheat when in use or charging.
The company ended up having to recall more than 2 million of the phones worldwide.
Samsung then starting making a new phone with a more protective battery, but reports of that overheating led the company to stop making the phone all together.
Professor Blanding believes the Note 7 was flawed in the way it was produced.
"That was a manufacturing defect. the inherit design was likely rock solid, but in the manufacturing, the manufacturing tolerances weren't quite what they're supposed to be and that caused some mistakes being made in the manufacturing process."
Blanding believes that recall could have been avoided if the proper research was done before the phone hit the shelves.
He says a lot of these products are made overseas, and companies may perform less testing if they can save money.
"Management wants to minimize the cost of testing, engineers want to test more - so there's always a tug of war."
The professor says the manufacturing defect is why you'll likely see a nationwide recall.
You may have heard from experts that you shouldn't use your phone while it's charging.
Blanding says it is more likely that even your cellphone that was made correctly could overheat while charging because all of the pressure that's put on the batteries.
The York College professor says don't use those cheap chargers you can buy online or at a grocery store
"If you buy sort of an off brand, off-market battery charger you're not assured that you have that right mix of the battery charging technologies."
As for the Samsung Galaxy Note 7, the company is asking everyone who owns one to shut it down immediately and return it.