In our previous article, we discussed the lifespan of cell phone batteries. As power banks are fundamentally created using similar technology, their behaviors parallel those of cell phone batteries. However, let’s examine the specifics of power banks in this exploration.
Similar to laptop and smartphone batteries, power banks also have a certain number of charge-discharge cycles before the device loses its capacity. Generally, lithium-ion batteries will be at 80% capacity after 500 cycles, while others will experience the same performance loss after 800-900 cycles. Afterward, the power bank can last for a long time, but there will be a gradual loss in capacity.
A full charging cycle is often considered to be the process of charging a battery from 0% to 100% and then discharging it back to 0%. There are multiple ways to consume a cycle, such as charging the device from 0 to 50% twice, 0 to 33% three times, and 0 to 25% four times. These are referred to as “partial cycles”. The frequency at which you charge and use a power bank will dictate how quickly a cycle is consumed, and with each consumed cycle, the power bank’s performance degrades.
On an average basis, a high-grade power bank has a lifespan of 4 to 5 years and can retain a charge for 4-6 months without substantial power loss. It’s important to note that these estimations are broad, and there are many factors that can sway the lifespan in either direction.
Power banks of smaller battery capacities or those constructed from inferior materials may have reduced lifespans. This can be due to the rapid consumption of charge-discharge cycles in smaller-capacity power banks and potential durability concerns with lower-quality construction. With large battery capacity, high-quality power banks can endure much longer. Larger power banks will need less frequent recharging, which also means the cycles aren’t consumed as rapidly.
Regarding how long power banks can retain a charge, most Li-ion and Li-poly power banks self-discharge at a rate of about 2% every month. This rate can increase to between 3% and 5%, contingent on the type and care they receive. Storing the power bank in a warm area will also cause the device to generate less power over time.
It’s essential to understand that not all power banks are created equal. Some manufacturers use superior-quality materials, while others opt for the most affordable components. This build quality can greatly influence the overall battery life. Typically, they come with a 1-3 year warranty upon purchase, providing a minimum period of assured high performance.
So, if your aim is to extract the longest possible life from your power bank battery, it would be wise to choose one from a reputable brand.
Different types of power banks and their lifespans
Given the fact that there are numerous different types of power banks with different build architectures, these will also have different lifespan estimations as well. Let’s have a closer look at different models and see how their features might also affect how long they last as well:
- Solar power banks. These types of power banks come with either an embedded solar panel or with multiple foldable solar panels. In order to be charged with solar power, these portable chargers need to stay under direct sunlight for extended amounts of time. This most likely means that the power bank will get very hot because of the direct sunray effects. The extra heat is a direct factor in reducing a battery’s lifespan, so we can expect these devices to last less than classic ones if they’re charged via solar power on a regular basis.
- Power banks with wireless charging. Whiles wireless charging is a very useful feature to have on a power bank, it does generate extra heat while it’s being used. If used constantly, it might degrade battery capacity, although its effect is much lower as compared to solar power banks used under direct sunlight.
- Power banks with built-in cables. Built-in cables in a power bank are very handy since you don’t have to always remember to take charging cables with you. Plus they reduce clutter. However, they also bring in an extra failure point. After a long period of use, these cables will get damaged, sometimes to the point that they won’t work at all. This basically renders the power bank unusable, even though the battery might still be working fine.
- High-capacity power banks. As previously hinted upon, power banks with large capacities can be expected to last somewhat longer than a regular-sized portable charger. Their extra capacity allows them to provide similar amounts of power with fewer charge/discharge cycles. The fewer the cycles, the longer the battery will last in the end. One thing to keep in mind, however, is that above a certain capacity, these portable battery packs are no longer allowed to be taken on planes.
Signs of a failing power bank
It’s very important to be able to tell when a power bank is at the end of its lifespan. This can either happen because the internal battery has maxed out its charge/discharge cycles or because of some other factors that render the power bank unusable. Here’s what to look for:
- Bloating/Swelling. Once you see the power bank case expanding, it’s a clear sign of a bloated battery. In internet terms, a swollen battery is called a spicy pillow. Once a battery reaches this stage it’s basically unsavable and should be properly disposed of as soon as possible.
- Excessive heating. If you notice that the power bank gets very hot even during regular usage, then it’s a sign of concern. It’s ok for battery packs to heat up slightly as they’re used, but once this gets so hot you can barely hold it in your palm comfortably, then you should take preventive measures. Continuous exposure to temperatures over 35 degrees Celsius (95 degrees Fahrenheit) can degrade the battery of a power bank over time. It’s important to avoid using or storing your power bank in hot environments for extended periods to maintain its performance and extend its lifespan,
- Smoke and/or smoke smell. If the power bank starts giving out smoke, or even smelling as such without any visual cues, it generally means it has had a short circuit or some other internal failure that has led to circuits being fried.
- The power bank does not hold any charge. If the battery degrades enough, then the power bank will not be able to have any electronic devices charged, regardless of how long it was connected to a power source. If you plug in your power bank to a wall charger for multiple hours and it won’t be able to charge other devices or will do so for a very short amount of time, you can safely assume that the battery has reached the end of its lifespan and it’s time to have it recycled.
Generally speaking, any time you notice a power bank is behaving strangely, or you suspect it to have been damaged (internal or external), it’s best to have a professional electrician have a look at it and asses its state. This is very important because in extreme cases, a portable battery pack can spontaneously self-combust or even explode.
How to recycle your old power bank
When a power bank reaches the end of its lifespan, proper disposal is crucial. Despite being inoperable, a spent portable battery pack should not be discarded in landfills due to the potentially harmful chemicals they contain. Also, in case of being punctured, it can generate landfill fires that are very difficult to put out and that can cause extremely toxic fumes to be released into the atmosphere.
In order to properly dispose of a portable charger, you should bring it to an electronics waste collection center. Depending on where you leave, supermarkets or malls in your area might have collection points where you can safely drop off any expended batteries, including power banks.
Guidelines for extending the lifespan of your power bank
1. Do not use it in extreme heat/cold
Overheating can cause any electronic device, like a laptop or power bank, to slow down or even fail. Using the portable charger in extremely hot or cold temperatures can damage the battery cell. As a side effect, this will cause the unit to shorten its lifespan. To ensure the portable charger lasts for a long time, you must use it where the temperatures aren’t too high or low.
2. Don’t let the power bank battery completely discharge to 0%
Frequently discharging the device to 0% can hasten the degradation of its battery, especially if it’s lithium-based. The original charge capacity will also decrease. It’s good practice to charge your device whenever it reaches between 10% and 20% of charge. This will ensure there is minimal damage to the cell.
3. Keep your power bank away from water
Most portable chargers aren’t waterproof, which can be problematic. If you leave your device in the rain or spill water on it, the unit will get flooded, causing it to be unusable.
4. Minimize the use of pass-through charging
Although pass-through charging (when the power bank itself is being charged while also charging another device) is a highly-useful feature in many power banks, it generates extra heat in the charging progress. The extra heat leads to increased inefficiency while charging and it’s also a key factor in reducing the overall battery lifespan.
5. Store your power bank properly
Proper storage is key for the long lifespan of your portable charger. Always make sure to store your portable chargers in places that are not in direct sunlight, and don’t have excess humidity and/or extreme temperatures. If your power bank came with a storage bag or case, make sure to always keep it there whenever it’s not in use. Besides helping with storage, the cases also offer protection against involuntary scratches and other types of accidental damage.
A power bank works like any other type of Li-ion battery and it has a similar lifespan given similar usage conditions. In time, their capacity will decrease naturally, but this can be hastened by improper usage. Keeping in mind the best-use recommendations, you will be able to expand the lifespan of your portable charger by a meaningful amount of time. However, please keep in mind that all suggestions in this article are general recommendations. We suggest always following any manufacturer recommendations, which can usually be found in the user manual that comes with your device.