Correct activation and charging/discharging methods for 26650 lithium batteries.

Correct activation and charging/discharging methods for 26650 lithium batteries.

When using lithium batteries, it should be noted that the battery enters a sleep state after being left for a period of time, at which point the capacity is lower than normal and the usage time is shortened accordingly. But lithium batteries are easy to activate, as long as they undergo 3-5 normal charge and discharge cycles to activate the battery and restore normal capacity. Due to the inherent characteristics of lithium batteries, they have almost no memory effect. Therefore, the new lithium battery in the user's mobile phone does not require any special methods or equipment during the activation process. Not only in theory, but also in my own practice, using standard charging methods from the beginning as a 'natural activation' approach is the best.

For the issue of "activation" of lithium batteries, many opinions suggest that the charging time must exceed 12 hours and be repeated three times in order to activate the battery. The statement that 'the first three charges should be charged for more than 12 hours' is clearly a continuation of nickel batteries such as nickel cadmium and nickel hydrogen. So this statement can be said to have been a misconception from the beginning. There is a significant difference in the charging and discharging characteristics between lithium batteries and nickel batteries, and it can be clearly stated that all the serious formal technical materials I have reviewed emphasize that overcharging and overdischarging can cause huge damage to lithium batteries, especially liquid lithium-ion batteries. Therefore, it is best to charge according to standard time and methods, especially not for over 12 hours of ultra long charging. Usually, the charging method described in the user manual is the standard charging method.

At the same time, long charging requires a long time and often needs to be carried out at night. Based on the situation of China's power grid, the voltage at night is relatively high and fluctuates greatly in many places. As mentioned earlier, lithium batteries are very delicate, and their ability to withstand fluctuations in charging and discharging is much worse than nickel batteries, which brings additional dangers.

In addition, another aspect that cannot be ignored is that lithium batteries are also not suitable for over discharge, which is also detrimental to lithium batteries.

Tools/raw materials

Lithium battery, nickel hydrogen battery, lithium battery charger, nickel hydrogen battery charger.

Steps/Methods
When should charging start during normal use
This statement can often be seen on forums, because the number of charging and discharging cycles is limited, so the battery should be fully charged as much as possible. But I found an experimental table about the charging and discharging cycles of lithium-ion batteries, and the data about the cycle life is listed as follows:
Cycle life (10% DOD):>1000 cycles

Cycle life (100% DOD):>200 cycles

DOD stands for Depth of Discharge. From the table, it can be seen that the number of rechargeable cycles is related to the depth of discharge, and the cycle life at 10% DOD is much longer than that at 100% DOD. Of course, if converted to the actual total charging capacity: 10% * 1000=100, 100% * 200=200, the latter's complete charging and discharging is still better. However, the statement made by the previous netizen needs some correction: under normal circumstances, you should charge according to the principle of using up the remaining battery before charging. But if your battery cannot last for two hours the next day, you should start charging in a timely manner. Of course, if you are willing to carry the charger to the office, that's another matter.

You need to charge to cope with expected inconvenience or when conditions do not allow charging, even when the battery still has a lot of remaining power, so you only need to charge in advance, because you have not really lost "1" charging cycle life, which is only "0. x" times, and often this x will be very small.

The principle of recharging after the remaining battery power is not to go to extremes. A widely circulated saying, like long charging, is "try to use up the battery as much as possible, preferably with automatic shutdown". This approach is actually only used on nickel batteries to avoid memory effects, unfortunately it has also been passed down in lithium batteries today. Due to excessive discharge of the battery, the voltage is too low, making it unsuitable for normal charging and startup conditions.

The correct approach to lithium batteries
In summary, my most important tip on the charging and discharging issues of lithium batteries during use is:
1. Charge according to standard time and procedures, even for the first three times;
2. When the battery level is too low, it is advisable to start charging as soon as possible;
3. The activation of lithium batteries does not require special methods, and they will naturally activate during normal use. If you insist on using the widely circulated "first three 12 hour long charging activation" method, it will not actually be effective.

Therefore, all the practices of pursuing 12-16 hour ultra long charging and using lithium batteries for automatic shutdown are wrong. If you have previously followed incorrect statements, please correct them in a timely manner, perhaps it is not too late.

matters needing attention

Under the condition of good self-protection and control circuit quality of the original charger, there is still a considerable guarantee for the protection of lithium batteries. So understanding the charging rules is the key, and in some cases, some concessions can also be made. For example, if you think the battery must be charged before you go to bed at night, you can also start charging before bedtime. The key to the problem is that you should know what the correct approach is and not deliberately follow the wrong statements.

The lifespan of electricity is generally 300-500 charging cycles. Assuming a complete discharge provides 1Q of electricity, without considering the decrease in electricity after each charging cycle, lithium batteries can provide or supplement a total of 300Q-500Q of electricity during their lifespan. From this, it can be inferred that if charged with 1/2 each time, it can be charged 600-1000 times; If you charge with 1/3 each time, you can charge 900-1500 times. Similarly, if charged randomly, the number of times is not fixed. In short, no matter how it is charged, the total amount of electricity replenished from 300Q to 500Q is constant. So, we can also understand it this way: the lifespan of lithium batteries is related to the total charging capacity of the battery, and not to the number of charging times. The impact of deep discharge and shallow charge on the lifespan of lithium batteries is not significantly different. So, when some manufacturers advertise, they say, 'A certain powerful lithium battery can be charged more than 1500 times.' This is purely deceiving consumers' ignorance.

In fact, shallow discharge and shallow charge are more beneficial for lithium batteries, and deep discharge and deep charge are only necessary when the power module of the product is calibrated for lithium batteries. So, products powered by lithium batteries do not have to be limited by the process, everything is convenient first, can be charged at any time, and there is no need to worry about affecting their lifespan.

Nowadays, mobile phones use lithium-ion batteries, so there is no memory effect problem and no need for activation. The first charge does not require more than 12 hours of charging like nickel batteries, only about 4 hours of charging. The lifespan of ion batteries is only related to the number of charges, and lithium-ion batteries can be charged about 1000 times. The standby time is related to usage. However, the seller of the phone said that the first three charging times need to reach 12 hours. What's going on?

1. How to charge a new battery
When using lithium batteries, it should be noted that the battery enters a sleep state after being left for a period of time, at which point the capacity is lower than normal and the usage time is shortened accordingly. But lithium batteries are very capacitive.
Easy to activate, the battery can be activated and restored to normal capacity after 3-5 normal charge and discharge cycles. Due to the inherent characteristics of lithium batteries, they have almost no memory effect.
Therefore, the new lithium battery in the user's mobile phone does not require any special methods or equipment during the activation process. Not only in theory, but also in my own practice, from the very beginning

The 'natural activation' method of charging using standard methods is the best.

For the issue of "activation" of lithium batteries, many opinions suggest that the charging time must exceed 12 hours and be repeated three times in order to activate the battery. This requires charging the first three times

The statement of 'more than 12 hours' is clearly a continuation of nickel batteries such as nickel cadmium and nickel hydrogen. So this statement can be said to have been a misconception from the beginning. Lithium and nickel batteries.

There is a significant difference in the charging and discharging characteristics of lithium-ion batteries, and it can be clearly stated that all the serious formal technical materials I have reviewed emphasize that overcharging and overdischarging can have an impact on lithium-ion batteries.

Pools, especially liquid lithium-ion batteries, cause significant damage. Therefore, it is best to charge according to standard time and methods, especially not for over 12 hours of ultra long charging

Usually, the charging method described in the phone manual is the standard charging method suitable for the phone.

In addition, lithium battery phones or chargers will automatically stop charging after the battery is fully charged, and there is no so-called "trickle" charging that lasts for more than 10 hours with nickel chargers. in other words

If your lithium battery is fully charged and placed on a charger, it will still be charged for nothing. And none of us can guarantee that the characteristics of the battery's charge and discharge protection circuit will never change and the quality will be foolproof,

So your battery will be hovering on the edge of danger for a long time. This is also another reason why we oppose long charging.
In addition, on some mobile phones, if the charger is not removed after a certain period of charging time, the system will not only not stop charging, but also start a discharge charge cycle. perhaps
The manufacturers of this approach have their own purposes, but it is clearly detrimental to the lifespan of batteries and mobile phones/chargers. Meanwhile, long charging takes a long time and often needs to be done at night,

Based on the situation of China's power grid, the voltage at night is relatively high and fluctuates greatly in many places. As mentioned earlier, lithium batteries are very delicate and more durable than nickel batteries in terms of charging and discharging

The ability to fluctuate is much weaker, which brings additional dangers.
In addition, another aspect that cannot be ignored is that lithium batteries are also not suitable for over discharge, which is also detrimental to lithium batteries. This leads to the following question.
2. When should charging start during normal use
On our forum, we often see this statement, because the number of charging and discharging times is limited, so the phone battery should be used up as much as possible before recharging. But I'm looking for
To an experimental table on the charge and discharge cycles of lithium-ion batteries, the data on cycle life is listed as follows:
Cycle life (10% DOD):>1000 cycles
Cycle life (100% DOD):>200 cycles
DOD stands for Depth of Discharge. From the table, it can be seen that the number of rechargeable cycles is related to the depth of discharge, and the cycle life at 10% DOD is much longer than that at 100% DOD. of course
If converted to the actual relative total charging capacity: 10% * 1000=100, 100% * 200=200, the latter's complete charging and discharging is still better, but the statement made by the previous netizen is
Make some corrections: Under normal circumstances, you should charge the battery according to the principle of using up the remaining battery before recharging, but if your battery is not expected to last the entire second day
During the day, you should start charging in a timely manner, but of course, if you are willing to carry the charger to the office, that's another matter.
And when you need to charge to cope with important events that are expected to cause busy communication, even if the battery still has a lot of remaining power, you just need to charge it in advance,
Because you haven't really lost "1" charging cycle life, which is only "0. x" times, and often this x is very small.
The principle of recharging after the remaining battery power is not to go to extremes. A widely circulated saying, like long charging, is "try to use up the battery of your phone as much as possible,
It's best to use automatic shutdown. This approach is actually only used on nickel batteries to avoid memory effects, unfortunately it has also been passed down in lithium batteries today. There used to be
An example where a person continues to use their phone without charging it even after receiving a warning of low battery level, leading to automatic shutdown. As a result, the phone in this example was charged and turned on later
There was no response and we had to send it to customer service for inspection. This is actually due to the low voltage caused by excessive discharge of the battery, resulting in the inability to have normal charging and startup conditions.
3. The correct approach for lithium battery smartphones
In summary, my most important tip on the charging and discharging issues of lithium battery smartphones during use is:
1. Charge according to standard time and procedures, even for the first three times;
2. When there is a low battery prompt on the phone, it is advisable to start charging as soon as possible;
3. The activation of lithium batteries does not require any special method, as they will naturally activate during normal use of the phone. If you insist on using the circulating 'first three 12 hour long charging activations'
The method, in fact, will not be effective.
Therefore, all the practices of pursuing 12 hour ultra long charging and using lithium battery phones for automatic shutdown are wrong. If you have done it according to the wrong statement before,
Please correct it in a timely manner, it may not be too late.
Of course, with good self-protection and control circuit quality of mobile phones and chargers, there is still a considerable guarantee for the protection of lithium batteries. So understanding the charging rules is the key, and in some cases, some concessions can also be made. For example, if you find that your phone needs to be charged before you go to bed at night, you can also start charging it before bedtime. The key to the problem is that you should know what the correct approach is and not deliberately follow the wrong statements.