Common Beliefs About Batteries
Grab your popcorn and your favorite fizzy drink, because we're here to tackle a lot of conflicting information that causes confusion about whether the batteries in the devices we constantly charge are being charged correctly. Some say charging overnight is best, while others argue that charging only up to 80% is better. Some even think that charging the battery to 5-10% during the day and storing it in the refrigerator is the best method. The harm of fast charging is still a subject of debate. Luckily, we're here to make sense of it all and provide you with the most comprehensive battery review. But we must warn you, the answers might not be what you want to hear. Are you ready?
Let's get started! First, here are 3 annoying facts:
- If you are charging your phone, you are slowly killing your battery. But don't unplug it just yet, because
- If you are using your phone and not charging it, you are still slowly killing your battery.
- Even if you turn off your phone and put it in a drawer, you are still slowly killing your battery.
Each charge-discharge cycle physically alters and degrades the internal structure of the battery. For example, modern phone batteries lose 20% of their capacity after about 500 full charge-discharge cycles. This corresponds to approximately one and a half to two years of use. This process also accelerates over time, so the next 20% loss happens even faster. But don't worry, there are some things we can do.
How Batteries Work
Let's get back to the fact that batteries are magical energy boxes. All batteries work through chemical reactions involving electron exchange between atoms. Each battery has two chambers called the anode and the cathode. The anode is a negatively charged chamber, while the cathode is positively charged. These chambers are not empty; they contain substances like graphite and cobalt oxide. However, the most important substance in a battery is lithium ions. These ions give up their electrons to power our devices, which is why batteries are called lithium-ion batteries. The battery's operating cycles and degradation rate can be increased from 500 to 1000, but we need to learn what to do for this.
In a fully charged battery, although hexagonal atomic cells are more suitable for lithium cells, there is also a more comfortable cathode with a cobalt oxide crystal structure. However, lithium ions cannot move because they want to escape from the comfortable cathode, but there is a liquid electrolyte barrier between them. The electrolyte only allows positively charged particles to pass through. Therefore, to complete the electron flow of the battery, we need to connect the positive and negative terminals. However, if a fully charged battery is not completely discharged and is continuously charged, it shortens the battery's lifespan. Also, overheating the battery or fast charging it affects its lifespan. If you want to extend your battery's life, the best method is to regularly charge it between 20-80% and protect it from extreme temperatures and cold weather conditions.
How Does a Battery Discharge?
When connected to the positive terminal in an electrical circuit, lithium's adorable electrons begin to detach using their own power and start a party. Electrons move from positive to negative along 5 paths, and other components follow them. They settle into the cobalt oxide crystal structure via the electrolyte, and the battery discharges.
How to Charge a Phone?
So how do we charge a phone battery? To charge the battery, we reverse the process and apply an electric current with a higher voltage to the positive and negative terminals of the battery. This causes electrons to flow back to the anode, refilling it, and the lithium ion becomes positively charged again.
However, all these electrochemical reactions do not pass without leaving a trace. First, some of the lithium ions, as they pass through the electrolyte, get stuck in a film-forming layer that thickens over time and becomes impermeable. Second, oxygen atoms detach from the cobalt oxide over time, causing oxidation. As a result, batteries can swell.
Correct Charging of Phone Batteries
We hear you, yes we can minimize some negative consequences. How? By controlling charging speed and temperature.
First of all, batteries don't like operating in hot or cold weather. We can use the battery down to -20 degrees, but the temperature should not exceed 60 degrees. So, the temperature of batteries should be exactly "Golden Ratio". Also, it's important to avoid charging the battery as quickly as possible, as this can shorten its lifespan. However, things are not that simple. If you try to charge a frozen battery, you could experience a 10-15% loss of capacity due to galvanic reaction. And if the battery swells, you might encounter surprises like several types of popcorn! At the same time, we need to protect the battery from high temperatures. Placing the phone in direct sunlight, charging it during intense gaming sessions, or feeling the device's casing heat up can shorten the battery's life. And finally, voltage control is also important. Voltage indicates the battery's charge level, so knowing how full it is crucial.
Batteries don't like to be charged when completely empty or completely full. Why? First, when the battery is empty, the voltage inside is very low. If you suddenly inject too much energy into it, the reaction rate will be very high due to the voltage difference, leading to a sudden increase in temperature. Even worse, this can rarely cause fire or explosion. This is like a dam breaking. Therefore, if your phone is completely empty and you plug it in to charge, the internal controller limits the charging speed for a while to balance the voltage. Then, a faster charge begins.
The opposite happens when the battery is fully charged. As the energy inside the battery increases, the voltage rises and resistance increases. As resistance increases, so does temperature. Therefore, when the charge reaches 80%, the charging speed drops to prevent overheating. Also, a rapid discharge is harmful to the battery. For example, if you play a game and your phone stays at 100% charge for 1-1.5 hours or if its charge is depleted, don't expect your battery to withstand this situation for a long time. We believe we have understood how we should charge our battery.
We have three options:
- Charging from zero to a hundred.
- Charging between 20% and 80%.
- Charging in small intervals throughout the day.
Tips for Proper Battery Use
Charging batteries until they are completely full or completely empty is not ideal. First, when a battery is completely empty, the voltage inside is very low. When energy is pumped in rapidly, voltage fluctuations are high, which can lead to overheating and pose a risk of fire or explosion. So, if you completely discharge your phone and plug it in, the controller inside your phone will limit the charging speed for a while and try to balance the voltage. During this time, a slow charge occurs. When the battery is fully charged, the energy level increases, which increases the internal resistance, raises the temperature, and can lead to overheating. Therefore, when the charge reaches 80 percent, the charging speed always drops. The last percentages of charge are particularly difficult. Electric vehicles are usually only charged up to 80 percent, which extends battery life by years.
Completely discharging your phone and plugging it in to charge overnight quickly depletes your battery. Also, during charging, the switches can wear out, and even when the device goes through several charge-discharge cycles, wear can occur. Apple and other companies implement features like optimum charging technology. Charging stops when it reaches 80 percent and then charges slowly for the remaining time. This prevents the charge/discharge cycle. Also, it's not good to keep your phone for several days without fully charging it. If you have a backup phone, it's better to charge it to 30-50 percent, which extends battery life. The 20-80 charging option seems more attractive, and since modern phones have a large battery capacity, it's not always necessary to charge to 100 percent. We advise you to pay attention to the battery's charge level.
Charging a smartphone battery from zero to one hundred is not a good option, as the battery is in its most unstable state when fully charged, its wear accelerates, the risk of overheating increases, and this shortens the battery's life. Electric cars are always charged to only 80%, which extends the battery's life by years. Keeping the battery between 50-70% makes its life much longer, so it's better to charge it slowly throughout the day. Wireless chargers can be a good option to extend battery life, but these devices have an efficiency of about 60% and should only be used in cool places. Fast charging, unfortunately, can damage the battery, and a study by Stanford, MIT, and the Toyota Research Institute has proven that fast charging shortens battery life.
Creating a perfectly optimized charging profile means creating one that charges the battery to 80% in 10 minutes and extends the battery life from 600-800 charge cycles to 1200. The profile starts with several independent charging cycles with high and strong current, then a constant current charge between 80% and 90%, and a voltage between 3-6 volts for a full charge. In general, there is no choice but to wait for phone manufacturers to implement such a profile, and this is a contribution that will significantly increase the phone's price.
In conclusion, regarding the correct charging of smartphones, we can say the following:
- First, avoid excessively high and low temperatures.
- Second, charge the battery frequently.
- Third, charge the battery before it is completely empty and before it is completely full.
We hope this information has been useful to you. We discussed how to properly charge smartphones and tried to provide as detailed information as possible.
