How long do lithium batteries last? Lithium battery life is a few years
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2022/02/26 14:57:44
"Lithium battery" means a battery with lithium metal or lithium alloy as the negative electrode, which uses a non-hydrolyzed solution. Gilbert T. Lewis first proposed and studied lithium metal batteries in 1912. In the 1970s, M.S. Wattingham proposed and began research on lithium-ion batteries. Because lithium metal has a strong chemical activity, so that its processing, storage, use, high environmental requirements. Therefore, lithium battery is not used for a long time will have an impact on life. With the development of science and technology, lithium battery has become the mainstream.
Lithium can be broadly divided into two types: lithium metal batteries and lithium ion batteries. The battery contains no metallic lithium ions and can be recharged. Lithium metal battery is the fifth generation of rechargeable battery, its safety, specific capacity, self-discharge rate and performance-to-price ratio are better than lithium ion battery. Companies in only a few countries are producing lithium-metal batteries because of their high technical requirements.
Lithium ion battery life
Lithium batteries can only be recharged up to 500 times?
I believe that most consumers have heard, the life of lithium battery is "500 times", 500 times charge and discharge, more than this time, the battery is "asleep", many friends in order to prolong the life of the battery, every time is completely exhausted when the battery charge the battery, so the life of the battery is really good? The answer is no. Lithium battery life is "500 times," not the number of charges and discharges, but the cycle of charge and discharge.
One charge cycle means that the full charge of the battery goes from full to empty and then back to full, not one charge. A lithium-ion battery, for example, consumes only half its capacity on the first day and is then recharged. If return like this the next day, use half electric quantity charge, charge twice in total, this counts a charge cycle only, do not calculate twice. So it usually takes several recharges to complete a cycle. At the end of each charge cycle, the battery capacity will decrease a little. However, the reduction is so small that good batteries retain 80 per cent of their original capacity after multiple charges, and many lithium-ion products continue to function after two or three years of use. Of course, lithium batteries still need to be replaced at the end of their lives.
By "500 cycles", the manufacturer is implementing about 625 chargers at a fixed discharge depth (say 80%) for a cycle of 500 chargers.
(80%*625=500)(factors such as decreased lithium battery capacity are ignored)
And because of various influences in real life, especially when charging the discharge depth is not constant, so "500 charge cycle" is only used for reference.
In other words, the life of a lithium battery is related to the completion of the charge cycle, and the number of charges is not directly related.
The simple idea of a lithium battery, for example, is that it consumes half its power the first day, and then recharges it. If return like this the next day, use half electric quantity charge, charge twice in total, this counts a charge cycle only, do not calculate twice. So it usually takes several recharges to complete a cycle. Each time a charging cycle is completed, the charge decreases slightly. However, the drop is small, as high-quality batteries can retain 80% of their original charge after multiple charges, which is why many lithium-ion products remain functional after two to three years of use. Of course, lithium battery life will eventually have to be replaced.
Lithium-ion batteries typically have a life span of 300 to 500 charges. Assuming that a full discharge provides Q, a lithium battery can provide or replenish a total of 300Q-500Q over its lifetime, without taking into account the drop in charge after each charge cycle. It turns out that if you use half of each charge, you can charge 600 to 1,000 times. If each charge is 1/3, then charge 900 to 1500 times. So, if you charge it randomly, the number of times is infinite. All in all, no matter how to charge, full 300Q to 500Q power is constant. Therefore, we can also understand that the life of lithium batteries is related to the total charging capacity of the battery, and has nothing to do with the number of charges. There is little difference between deep charge and shallow charge in lithium battery life.
In fact, shallow discharge and shallow charge is more favorable to lithium, and only when the power module of the product is calibrated for lithium, deep discharge and deep charge is necessary. Therefore, the use of lithium electric power products do not have to stick to the process, everything is mainly convenient, charging at any time, do not worry about the impact of life.
If lithium is used at a specified operating temperature above 35°C, the battery will continue to lose power, which means that the battery will not last as long as usual. If the device is charged at this temperature, the battery will suffer more damage. Even storing a battery in a hot environment will inevitably lead to a corresponding loss of battery quality. Therefore, keeping the operating temperature as appropriate as possible is a good way to prolong the life of lithium batteries.
If lithium is applied to the low temperature environment below 4℃, it can also shorten the use time of the battery. Some mobile phones can not even charge in the low temperature environment, which is the reason for lithium. But don't worry too much, this is only a temporary situation, unlike in high temperature environments, once the temperature rises, the molecules in the battery heat up and immediately return to their original charge.
To get the most out of lithium-ion batteries, they need to be used frequently to keep electrons flowing. If lithium is not used frequently, we must remember to complete a charging cycle every month, a battery calibration, that is, deep deep charge.
Conventional appellation is "charge and discharge cycle", is not equal to "recharge" times cycle refers to the battery from electricity to light, it's a cycle, if your battery from full charge state, consumes one over ten of the electricity, then full of, this is a one over ten of circulation, such as 10 times, basically, even if a cycle. Similarly, starting from a full charge, using half the charge, then using half the charge again, is a cycle, and that cycle is two charges. Thus, the cycle only depends on the "accumulated discharge of the battery", and is not directly related to the "charge times".
In addition, the number of charge and discharge cycles in this standard does not mean that the battery can no longer be used, but that after many cycles, the storage capacity of the battery decreases to a certain extent,
For example, a certain type of lithium battery, its nominal charge and discharge cycle is "500 times, the capacity is not less than 60% of the nominal capacity"
That is, after 500 cycles, the maximum charge of the battery is only 60 percent of the new battery, and the performance drops to a certain point, that's what it means.
Lithium battery has no fixed charge times limit, the battery produced by regular manufacturers can charge and discharge at least 500 times, and the capacity is maintained at more than 80% of the initial capacity, one charge a day can be used for 2 years. In general, the battery becomes less durable after 1,000 charges.
Mobile phone battery maintenance:
Each full charge, reduce the number of charging, prolong the battery life.
There is no need to fully discharge the battery, which usually needs to be recharged below 10%.
Use the original charger, not the universal charger.
Do not use your mobile phone while it is charging.
Don't overcharge, stop charging when the battery is full.
Yes, according to the experimental results, the life of lithium batteries will continue to decline with the increase of charge times, the general charge times of lithium batteries in 2000-3000 times.
Cycle is use, when we use the battery, we should consider the use time of the battery, in order to measure how long the rechargeable battery can use such a performance, the cycle number is defined. Because the tests under different conditions are not comparable, the actual use of users varies greatly, so the definition of cycle life must be standardized for comparison.
Testing conditions and requirements for the cycle life of lithium batteries stipulated by the State: Under the condition of ambient temperature 20℃±5℃,1C charging, when the battery terminal voltage reaches 4.2V charging limit voltage, instead of constant voltage charging, until the charging current is less than or equal to 1/20C, stop charging, use 0.5h~1h,1C current discharge to 2.75V termination voltage, discharge end, 0.5h~ 1H use, The charge-discharge cycle is carried out again until the continuous discharge time is less than 36min. The service life is considered to be terminated and the cycle times must be greater than 300 times.
Interpretation of national standards:
This definition provides that the cycle life test shall be carried out in a deep charge and deep discharge manner.
According to the specified cycle life of lithium battery in this mode, the capacity is still more than 60% after ≥300 cycles.
However, the number of cycles produced by different cycle systems will vary greatly. For example, if the above other conditions remain unchanged, the cycle life of the same type of battery can be tested by changing the constant voltage from 4.2V to 4.1V, so that the battery is no longer in deep charge mode and eventually reaches full charge.
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