Power banks are incredibly useful gadgets. They’re lifesavers for people on the go, keeping our smartphones charged when we’re nowhere near an outlet. But if you’ve ever owned a power bank long enough, you might have noticed it getting bulkier or even starting to swell. This change in shape can be alarming, and it raises the question: why do power banks swell, and what can you do to prevent it? Here, we’ll discuss common reasons behind power bank swelling, the risks involved, and practical steps to ensure the safety and longevity of your power bank.
So, Why Do Power Banks Start to Swell?
The primary reason power banks swell is due to a malfunction within the lithium-ion or lithium-polymer battery cells. Most modern power banks use lithium batteries because they’re compact, rechargeable, and able to store a significant amount of power. However, these batteries are also susceptible to chemical reactions that can cause them to swell when the conditions are less than ideal.
When lithium batteries are overcharged, exposed to extreme heat, or damaged, the chemical reactions within them can produce gases like carbon dioxide and oxygen. These gases build up inside the battery, causing it to expand and, ultimately, swell. Once a battery starts to swell, it’s a red flag that something has gone wrong internally, and ignoring it can lead to safety hazards.
1. Overcharging
Overcharging a power bank is one of the most common causes of battery swelling. Power banks are designed to be charged up to a certain voltage, but when they’re plugged in for too long, the internal battery cells can go beyond this safe limit, resulting in excess heat and gas production. While many power banks come with protection circuits to prevent overcharging, not all do, and even high-quality ones can fail over time.
Solution: To avoid overcharging, try not to leave your power bank plugged in for extended periods, especially overnight. As soon as it’s fully charged, unplug it. Some power banks come with auto-shutoff features, which stop charging when the battery reaches its full capacity, so opting for a model with this feature can be a safer bet.
2. Heat Exposure
Heat is another major factor that can lead to battery swelling. Power banks, like all lithium-based batteries, are highly sensitive to temperature changes. Leaving your power bank in a hot car, in direct sunlight, or near heat-generating devices can raise its internal temperature, causing the battery cells to become unstable and produce gas.
Additionally, using a power bank while it’s charging (a process known as pass-through charging) can create heat buildup. The combination of charging and discharging simultaneously puts extra strain on the battery, increasing the chances of overheating.
Solution: Keep your power bank in a cool, dry place and avoid exposing it to high temperatures. Try not to use it while it’s charging, as this can generate more heat and wear down the battery faster. If you’re outdoors or in hot conditions, store your power bank in a shaded or insulated bag to protect it from the sun.
3. Physical Damage / Wear & Tear
Physical damage is another reason why power banks might swell. Dropping a power bank or exposing it to water can disrupt its delicate battery cells, leading to swelling or even short-circuiting. While some power banks are designed to be more rugged and shock-resistant, most are still quite sensitive to impact and can suffer internal damage from a single drop.
Even without visible damage, the daily wear and tear of constantly charging and discharging the battery will eventually degrade it. As the battery cells age, they become more prone to chemical imbalances, which can lead to gas production and swelling over time.
Solution: Handle your power bank with care and try to avoid dropping it. If possible, buy a protective case or choose a model that is water-resistant and shockproof. Remember that all batteries have a limited lifespan, so after a couple of years, it might be worth investing in a new power bank.
4. Using Low-Quality or Mismatched Chargers
Using cheap or low-quality chargers, or chargers that are incompatible with your power bank, can contribute to battery swelling. Low-quality chargers may not regulate voltage properly, leading to irregular charging patterns, overheating, or overcharging. This not only shortens the lifespan of the battery but also increases the risk of swelling.
Solution: Stick to using the charger provided by the manufacturer, or if you’re using a replacement, make sure it’s compatible with your power bank’s specifications. High-quality chargers may cost a bit more, but they’re worth the investment to keep your device safe and functioning properly.
Why You Shouldn’t Ignore a Swelling Power Bank
If your power bank starts to swell, it’s imperative not to ignore it. Continuing to use a swollen power bank is risky. The battery could leak or, in extreme cases, explode, causing injury or damage to your belongings. A swollen battery also releases harmful gases and chemicals, which can be a health hazard if inhaled or absorbed through the skin.
Steps to Take if Your Power Bank is Swelling
- Stop Using It Immediately: If you notice any swelling, disconnect the power bank from all devices and stop using it right away. Continuing to use a swollen power bank increases the risk of leakage or explosion.
- Dispose of It Safely: Lithium batteries should never be thrown in regular trash due to the risk of combustion. Take your swollen power bank to a certified electronics recycling center. Many tech stores and electronic shops offer battery recycling services for safe disposal.
- Don’t Attempt to Fix It: A swollen battery isn’t something that can be repaired. Opening the power bank casing or trying to flatten the swelling is extremely dangerous and can lead to battery rupture or explosion. Once it’s swollen, it’s time for a new power bank.
How to Prolong the Life of Your Power Bank
To prevent swelling and keep your power bank in good shape, here are some tips:
- Avoid Full Discharges: Instead of letting the battery drain completely before charging it, try to keep it between 20% and 80% for optimal performance.
- Use Original Cables: Using the original cables provided by the manufacturer can help maintain consistent charging and reduce the risk of overheating.
- Charge in a Cool Place: Charging in a well-ventilated, cool area reduces heat buildup and helps prolong battery life.
- Don’t Leave it Unused for Long Periods: Batteries degrade faster if left unused for too long. If you have a backup power bank, make it a habit to charge and discharge it every few months.
Power bank swelling is a result of several factors, from overcharging and heat exposure to using low-quality chargers. While power banks are convenient and reliable when handled correctly, they require care and attention to ensure long-term use and safety.
Taking good care of your power bank not only prevents swelling but also extends its lifespan, giving you more value for your investment and ensuring you always have backup power when you need it. Just remember: if you do notice any signs of swelling, don’t risk using it further. Replace it and dispose of the old one responsibly. With these steps in mind, you can enjoy reliable power on the go without worrying about battery mishaps.
