What effect does low temperature have on lithium batteries?

Conditions of Use of Lithium Batteries
Such a high energy density lithium battery, its use should be very careful. A little carelessness can affect the lifespan, or it may explode and catch fire, such as Samsung's battery door. In all operating conditions, voltage and temperature are the two most important relevant conditions
The horizontal axis is voltage, and the vertical axis is temperature. It can be seen that in this quadrant, there is only a small safe area in the middle of the large red warnings that indicate various terrible consequences. It is the comfort zone of lithium batteries, and getting out of it poses risks:
Both higher than 4.2V and lower than 3.4V will have an impact on the life of lithium batteries. Higher than 4.2V is called overcharge, which will have an irreversible impact on battery life. In severe cases, it will cause thermal runaway (thermal runaway), which may cause bubbles, liquid leakage, fire and explosion.
The low temperature causes the reduction of the internal resistance of the electrolyte of the battery cell, and may form lithium condensation on the cathode, which irreversibly affects the battery life. High temperature may cause explosion, etc., which is very dangerous.

Protection of Lithium Battery Packs
All lithium batteries have self-protection circuits. A simplest protection circuit needs to contain at least the following elements:
Protection IC: With bidirectional charging and discharging protection, the circuit is disconnected when overcharged or overdischarged for safety.
Fuse: Fusing the current in an emergency is the last insurance.

Conclusion: Lithium battery chargers should not be charged all the time
The first use should be fully charged three times to activate the lithium battery. Wrong, lithium batteries have no memory effect and do not need to be activated.
It is best to recharge after use up. Wrong, cycle life is not a vulgar number of recharges, but a whole cycle, that is, the process of running out of battery power and then refilling it, rather than plugging in the charger and unplugging it once. Can be recharged at any time. If it is used up and recharged, it may also lead to over-discharge and affect the battery life if it is left for too long.
Don't keep charging, just unplug it when it's done. A few are right, most are wrong. General mobile phone charging is not a simple constant voltage charging, but in order to prolong the battery life, there are optimized charging algorithms, including CC, CV and MC and so on. After judging that it is full, it will not keep rushing all the time. Don't worry at all, you can always plug in the power supply. Due to the lack of charging management equipment for some cottages and low-cost devices, it is recommended to charge them as soon as possible.
Charge your phone when you are not using it. correct. When the lithium battery is not used, the power will flow quietly, and it will be over-discharged when it is lower than 2.0V, which will seriously affect the battery life. It is best to charge regularly.