How to Handle a Swollen Battery in Your Laptop or Smartphone
It may start with something subtle, like a trackpad that just doesn’t click like it used to, or a laptop that doesn’t quite sit flush to the desk anymore – or it may be something blatantly obvious, like a notebook case that starts to warp and grow like a bag of popcorn in the microwave. Either way, what you’re dealing with is modern technology’s equivalent of the plague – a swollen lithium-ion battery. Unlike the plague, a swollen battery isn’t contagious, but like the plague, it’s always extremely dangerous. In this article, I’ll show you to deal with a swollen battery in your laptop, smartphone, or other high-tech device.
When did lithium-ion batteries become so prevalent?
Lithium-ion batteries are the power source for nearly all portable electronic technology these days. Like all batteries, lithium-ion batteries use a chemical reaction to store electrical power, and to provide electrical power to devices like smartphones and laptops. Development of lithium batteries actually began more than a century ago, but it was not until the 1970s that commercially-viable designs began to become practical to build. For quite some time, lithium battery development was stalled for safety reasons, as the metallic lithium used in the batteries had a tendency to form dendritic spines during cycling, which would in turn lead to rupture of the battery accompanied by fire. It was not until 1991 that Sony commercialized the first lithium ion battery, using free lithium ions rather than a metal substrate, which has led to the rapid growth of this battery technology in high-tech applications.
Why are lithium-ion batteries useful?
Lithium-ion batteries have some major advantages over other battery chemistries. Lithium-ion batteries are very energy dense, meaning that a large amount of electrical power can be stored in a relatively small and light space. The batteries have very long cycle durations and shelf life, meaning that they can be charged and discharged many hundreds of times before losing efficiency. They are easy to charge with inexpensive, low-tech battery chargers, and can be charged fairly quickly relative to other battery types. They have low self-discharge rates, meaning that a charged battery can sit for some time between uses without losing significant amounts of power.
There are some disadvantages to this battery chemistry. The largest disadvantage is that the batteries have the potential to enter a thermal runaway cycle (i.e. they catch fire) is the battery is put under certain kinds of stress; for this reason, any application using a lithium-ion cell must include circuitry that can detect these runaway cycles and shut the battery down. Lithium-ion batteries are vulnerable under high-temperature conditions, and can’t be stored at high voltages. In cold temperatures, the batteries function just fine, but cannot be rapidly recharged without severe damage to the battery. Finally, the thermal hazard that a badly-built battery represents means that transporting them requires precautions and is subject to numerous regulations.
Despite these disadvantages, the advantages of lithium batteries are such that the technology has become extremely useful, and lithium-ion batteries are used in practically all high-tech applications.
What causes a swollen battery?
There are a number of possible reasons that a lithium-ion battery can swell. The most common cause is an overcharge of the battery, which causes a chemical reaction between the electrodes and the electrolyte, resulting in the release of heat and gases that expand inside the battery, causing the casing to swell or even to split open. Swelling can also result from a poor cell build, somewhat common in very low-grade batteries from some overseas manufacturers. Mechanical damage to the battery, such as striking a hard surface and denting the casing, can definitely cause a swelling condition, as can exposure to excessive high temperatures. Finally, lithium-ion batteries can swell as a result of a deep discharge of the cells; usually lithium-ion batteries are governed by circuitry (sometimes called a battery management system or BMS) that prevents this from happening.
In any event, whatever the primary cause of the swelling, what occurs inside the battery is that too much current is present inside a given cell of the battery. According to an article by Don Sadoway, professor of materials chemistry at MIT in Electronics Weekly: “There are strict limits on how much current can be put through a lithium-ion cell. During normal charging, you never see metallic lithium, which is inherently unstable. But during overcharging, the lithium builds up faster than it can dissipate. The result is that metallic lithium plates up on the anode. At the same time, the cathode becomes an oxidizing agent and loses stability.”
This process produces a great deal of heat, which in turn warms the gases inside the battery, causing them to expand. Lithium-ion batteries are not designed to be ventilated, and so the the battery’s casing expands with the gasses, distorting and warping its appearance into that familiar swollen look.
Because these design issues are well-understood at this point, battery designers and manufacturers build batteries with the possibility of this reaction in mind. Batteries are built to withstand a large amount of expansion, and circuitry is almost invariably included in battery controllers to regulate the battery’s charge and to shut off the power if unsafe conditions are detected. However, no safeguards are 100% effective, and it’s possible to end up with a swollen battery despite every precaution.
How to avoid a swollen battery
There are a number of things you can do to minimize the risk of a battery failure. You can’t completely eliminate the risk, simply because there is always the possibility of a factory defect, but owner mistreatment of the battery is by far the most common cause of a swollen battery. In addition to preventing battery swelling, these suggestions are also good for optimizing your battery life.
Always use the appropriate power charger. Use only quality chargers from reputable manufacturers, not third-party chargers built by a no-name factory. If you don’t have the original charger that came with a battery, then get a charger with the exact same power output as the original charger. Just because the charging plug fits does NOT mean that a charger is appropriate for your specific battery configuration!
Don’t leave your device plugged in all the time. This is particularly an issue for laptop users who primarily use their laptop at home. The device sits plugged in to the wall all the time, and the battery isn’t given the opportunity to exercise its capacity. For Mac users, the free tool coconutBattery can help remind you when it’s time to unplug your power cord and let the battery complete a discharge and recharge cycle. Windows users can check out a number of options that offer similar functionality, such as BatteryCare (free) and BatteryBar Pro ($8).
Keep your battery stored in a cool, dry environment. Occasional use in the sun is fine, but don’t store your laptop or smartphone in a hot car, or humid environment.
Replace your battery if it becomes exhausted or damaged. Batteries are consumable products; they’re meant to slowly degrade in performance over time. So if your battery is no longer holding a charge, or if it becomes damaged due to a drop or impact, make sure to replace it, before a catastrophic failure can occur.
How to deal with a swollen battery
If you suspect that your device has a swollen battery, the first step is to exercise caution. Puncturing a battery in any state is incredibly dangerous, but swollen batteries are especially vulnerable to compromise as their casing is already under stress from the built up gasses within. In short, handle any device with a suspected swollen battery with care.
Next, if your device has a user-removable battery, you can try to carefully remove it. Note that the battery’s swollen casing may make removal difficult. If you encounter any unusual resistance to removing the battery, stop and follow the advice below for those with devices containing non-user-removable batteries. If, however, you are able to successfully remove the swollen battery, place it in a safe, cool container so that it won’t be vulnerable to puncturing.
Do not discard the battery in the trash or elsewhere. Doing so can severely injure the health of sanitation workers who may come into contact with the battery, as well as the environment. Instead, always dispose of batteries — swollen or not — at an authorized battery disposal facility. Many computer repair locations have the equipment and procedures to safely handle swollen batteries. For example, if you have an Apple MacBook Pro, take the battery to your nearest Apple Store. Other electronics retailers, such as Best Buy, also offer recycling and disposal services. Just make sure that you inform the employees that you are recycling a swollen battery so that they can take the proper precautions (don’t just drop the swollen battery in a battery recycling kiosk). If you can’t find a suitable location to dispose of your battery, contact your local government for instructions.
If your device does not have a user-replaceable battery, such as some recent laptops and smartphones, don’t try to remove it yourself. Simply take the entire device to one of the locations mentioned above for assistance. Note, however, that until your swollen battery is replaced, you shouldn’t connect your device to power or use it. Swollen batteries can explode if not properly dealt with, so you don’t want to take any actions that may hasten the arrival of this unpleasant event.
Above all else, be safe. Don’t try to puncture the battery, don’t leave it in a hot car or a location where it could be picked up by children or pets, and don’t ignore it. Your laptop or smartphone will likely continue to work with a swollen battery, at least for a little while. But ignoring the problem and continuing to use the battery will only increase the risk of a puncture or explosion, which could result in devastating injuries. Battery leaks and explosions are rare, to be sure, but you don’t want to test the odds.
We have more resources for portable technology users.
Do you own a Macbook? Then you should definitely check out our guide to knowing when to replace the battery on your Macbook.
If you need to pull a battery out of your iPhone, see our guide to iPhone battery removal.
iPhone users will want to see our walkthrough on monitoring your battery usage and health on iOS 12.
Apple product owners should check out our tutorial on checking your iPad, iPhone and Macbook battery health.
Got a Nintendo Switch? Be sure to read our guide to extending battery life on your Nintendo Switch.