No one was injured in the Oct. 4 mishap at the family's Philadelphia home. But the Karaseks say the device was to blame for a blaze that might easily have been much worse.
"We were fortunate," Peggy Karasek said. "We were able to contain the fire just to that area of the room."
Bad batteries have made 2004 a year of living dangerously with cell phones. Watchdog groups devoted to the safety of consumer products say they've fielded dozens of reports this year of cell phone meltdowns that have resulted in injury and property damage.
Defective or counterfeit batteries have caused nearly all of the reported incidents, while others were caused by dropped phones, according to the U.S. Consumer Product Safety Commission.
The incidents have involved a tiny percentage of the 170 million cell phone subscribers in the United States. But consumer advocates believe that the increase in battery failures points to a worrying trend.
"What we've seen over the years is a spike in bad batteries of many kinds," CPSC spokesman Scott Wolfson said. "This year, we've seen cell phones explode, and there have been reports of fires and of people getting burned on different parts of their bodies."
Treacherous batteries aren't the only potential dangers cell phone users face. Cellular phones have long been rumored to contribute to tumors in the brain, a notion that gained some credence last week with a report from a Swedish research institute. The U.S. Food and Drug Administration says that though scientific evidence has not demonstrated that health problems arise from the use of wireless phones, "there is no proof...that wireless phones are absolutely safe."
Cell phones are also at the center of a debate about driving safety. Officials in some states have outlawed the use of cell phones while operating a car, for fear that phones could cause distractions and thus accidents.
The threat of a cell phone turning into a sort of Zippo lighter is rare, but real.
Lithium-ion batteries, used in most cell phones, can overheat in certain circumstances--with a short circuit, for example. If the temperature rises slowly, the battery case may melt. If it rises too rapidly, however, it can generate sufficient pressure to create a small explosion.
Most batteries produced by authorized manufacturers include fail-safe protection against a meltdown, including vents to release excess heat and a temperature-activated shutdown switch. Counterfeit batteries may not include either of these features, increasing the likelihood of an explosion, experts said.
Even authorized batteries can fail, however--if, for example, heat vents become blocked. In at least one case, investigators concluded that an authorized battery carried outside of a phone short-circuited and exploded after its metal contacts pressed up against pocket change for an extended length of time. A dropped phone can also trigger an explosion, depending on how the device lands.
The threat of cell phone battery malfunctions is coming into focus a little more than a year after reports of exploding phones first began to surface in the United States, following back-to-back incidents in the Netherlands. In August 2003, a 33-year-old Dutch woman was injured when her Nokia phone exploded in her hands. Two months later, a Dutch supermarket employee suffered burns on his legs when a Nokia handheld exploded in his pants pocket.
Reports of battery meltdowns have continued to pile up since then, with explosions and injuries linked to various manufacturers.
Edward Edgar, a 35-year-old independent businessman from Sweetwater, Texas, says that in February, he was at home charging his LG 5250 phone when he heard a loud pop, then a crackling sound.
"The phone exploded from inside," he recently recalled. "It sounded like a small firecracker had gone off." Luckily, Edgar wasn't injured, and, unlike the incident involving the Karaseks, the mishap didn't start a fire.
LG has said it's been the victim of a third-party manufacturer that produced counterfeit batteries for LG phones.
In June, fist-size flames from a Kyocera Wireless cell phone seriously burned a 16-year-old California girl's legs.
The CPSC reported that some batteries in Kyocera 7135 phones have short-circuited and heated up enough to trigger a built-in safety mechanism that vents superheated gases to avoid an explosion. "It was unrelated to anything Kyocera Wireless sold or manufactured," a Kyocera Wireless representative said.
On Dec. 6, a Philadelphia-area man suffered second-degree burns on his leg when the spare cell phone battery in his pocket vented, the CPSC said. In three other instances, the batteries were connected to the Kyocera 7135, but the phones were not being held and weren't close to a person when they vented, according to Kyocera.
In January, Kyocera issued a voluntary recall of cell phone batteries associated with affected Kyocera Wireless model 7135 smart phones sold between September and December. The company also said it has doubled the number of batteries it X-rays, weighs and otherwise tests to weed out defects.
Kyocera Wireless has been "remaking our whole attitude to batteries," said a company representative.
Steve Largent, president of the Cellular Telecommunications & Internet Association, a cell phone lobbying group, said the industry as a whole is also taking the incidents of battery explosions seriously and is working to find solutions.
"We want to ensure that consumers, who are recognizing wireless as an essential tool in their everyday lives, can continue relying on wireless phones as a safety tool and for business and personal communications," he said.
In the past few weeks, the IEEE, a well-respected standards group, took the initial steps to create universally accepted safety criteria for cell phone batteries. Meanwhile, chipmakers are adding new security measures to thwart battery counterfeiters. Counterfeit batteries are in huge supply--5 million of them have been confiscated this year, according to Nokia.
Ideally, bogus batteries would never turn on any cell phones, and chargers would refuse to recharge the counterfeit energy sources, said Dave Heacock, vice president of Texas Instruments' portable power unit. "The industry has made some good headway," he said.
For its part, the CPSC wants the government to crack down on ports and warehouses to discover the bad batteries before they reach consumers. It also continues to investigate cases involving counterfeit batteries.
Some handset makers are tightening controls over third-party suppliers of batteries, especially suppliers based in China, a country to where many counterfeit and defective batteries have been traced.
That promises to be tough fight. LG Mobile Phones claims that it can't find the manufacturer in China that produced counterfeit batteries that bore the LG Mobile Phones logo and were ultimately sold at various wireless carriers' stores as spares or replacements. About 18 phones using the batteries overheated, some causing burnt car seats and floorboards.
The China-based company is "no longer in business, and we can't find them. They have disappeared," an LG spokeswoman said. LG is suing two U.S. distributors of the batteries, she added.