Mobile phone users rarely consider the mini power plants that keep their devices multi-tasking all day. Now those rechargeable lithium-ion batteries are big news, thanks to Samsung’s recall of the latest version of its big-screen Note 7 phones following more than 100 reports of fires or explosions. As batteries have gotten both smaller and more powerful, lithium-ion woes have been popping up more frequently. The batteries that power much of the information economy have led to recalls of laptops, bans of hoverboards and a delayed jetliner debut.
1. Why are Samsung phones catching fire?
The U.S. Consumer Product Safety Commission said the compartment for the battery is a little too small and pinches the battery, causing short circuits and overheating. Samsung previously said that a manufacturing flaw brings negative and positive poles into contact, triggering excessive heat. The company said in a different report that a piece of technology that separates the electrodes might be thinning out, leading to short-circuiting.
2. Why don’t the phones just stop working?
The Note 7 features a larger battery than its predecessor, one that can store 3500 milliamp hours of electric power, compared with 3000 mAh for the Note 5. More power means more danger when something goes wrong. Rather than simply malfunction, these batteries have enough stored energy to catch fire or explode.
3. Are other phones dangerous?
Potentially, but it’s a long-shot. The iPhone 7 Plus, the Note 7’s main competitor, has a less-powerful 2900 mAh battery, which reduces the danger if the battery malfunctions. In general, lithium-ion batteries are safe because manufacturers have gone through rigorous testing of the designs. But smartphone makers have pressed for smaller and more powerful battery packs, as well as a fast-charging feature, which puts additional stress on the batteries. A number of other phones have that feature, while the iPhone does not.
4. How do lithium-ion batteries work?
Lithium ions move from the negative pole (anode) to the positive pole (cathode) while discharging and vice versa while charging. Between the electrodes is a liquid chemical, an electrolyte, and a permeable membrane, a separator, that allows only ions to pass through. One way to increase the power capacity has been to make that separator thinner, increasing the chance that the wall will be penetrated, according to Martin Reynolds, a vice president at research firm Gartner.
5. How else have lithium-ion batteries caused problems?
A Sony Corp.-made battery pack that overheated led to the recall of millions of laptops made by Dell Inc., Toshiba Corp. and others in 2006. Problems with the batteries also triggered a global grounding during the debut of the Boeing Co.’s 787 Dreamliner in 2013. Earlier this year, about 500,000 hoverboards were recalled in the U.S. by 10 companies after reports of overheating, sparks and fire.
6. How is Samsung responding?
It halted sales of the Note 7 and is rolling out recall programs around the world. In most countries, customers can opt to wait for a new phone and use a loaner, or exchange their phone for a Galaxy S7 and a partial refund. A software update will be available for users in South Korea on Sept. 20 that will limit the charge on Note 7 batteries to 60 percent of capacity. The U.S. recall, announced on Sept. 15, affects about 1 million Note 7 devices. The company promised to get the new phones to retailers in the U.S. by Sept. 21.
7. What does this mean for Samsung?
The recall represents a big setback for the South Korean electronics giant in its battle with Apple, whose iPhone 7 hit stores Friday. The Note 7 stood out with its stylus, large edge-to-edge display, iris scanner and better waterproofing techniques. Samsung rolled out the device in August, just before Apple unveiled the ne iPhone. Samsung has now lost much of the momentum it built in smartphone sales. Instead of celebrating a triumphant launch of a premium product, the company has had to deal with consumer complaints and employees’ feelings of humiliation. The recall needs to be successful for Samsung to recover its reputation.
The Reference Shelf
- A story on the perils of building better batteries.
- An explainer on batteries.
- A look at Samsung’s challenge in rebuilding trust.
- A Bloomberg View column on hoverboards and problems with their China-made lithium-ion batteries.