Why are ternary lithium batteries more suitable for home electric vehicles?

A, low temperature discharge performance is better

China's vast, climate is complex, from the three northeastern provinces in the north to the temperature changes at the southernmost tip of Hainan islands are abundant.In Beijing, for example, as the main electric car market, Beijing summer high temperature around 40 ℃, while winter is basic about 16 ℃ below zero, even lower.This temperature range is suitable for low temperature performance obviously better ternary lithium battery.And pay attention to high temperature resistant performance lithium iron phosphate batteries in winter in Beijing would seem to be some lack of power.

"Relative capacity of 25 ℃" refers to the different temperature conditions to devolve electricity capacity and 25 ℃ when the ratio of discharge capacity.The numerical can accurately reflect the attenuation of battery under the condition of different temperature range, the more close to 100%, the better the cell performance.

Can see from the above, 25 ℃ as a benchmark in normal temperature, two types of cells in 55 ℃ high temperature lowering electricity and room temperature 25 ℃ to devolve electricity, almost no difference between the discharge capacity.But at 20 ℃ below zero, the ternary lithium battery and lithium iron phosphate battery has obvious advantages compared.

Second, the energy density is higher

According to the domestic ternary material 18650 cylindrical battery bibcock enterprise --Bak battery information provided, the battery energy density of 18650 has reached 232 wh/kg, the subsequent will further increase to 293 wh/kg.Compared to the current domestic mainstream of lithium iron phosphate battery energy density is only 150 wh/kg, according to the domestic battery industry experts, within the next few years, the energy density of lithium iron phosphate batteries could reach 300 wh/kg of hope is very slim.

Different from huge electric buses, for household electric vehicles, space is always the first.Low energy density of lithium iron phosphate batteries will occupy the already not much space, and because the quality of the heavier, when use the discharge range will be affected by the relatively large.Relatively high energy density of the ternary lithium battery in the solution to the problem of weight at the same time also save the space for family car.

Third, charging efficiency is higher

In addition to life, charge is also an important link of electric vehicles in the practical use, and the ternary lithium battery in the lithium iron phosphate battery charging efficiency has a very big advantage.

Currently on the market more common way of charging for constant current constant voltage charging.General in charge at the beginning of the first USES the constant current charging, the current is bigger, the charging efficiency is relatively higher.And after the voltage reaches a certain value, reduce the current to constant voltage charging, so that we can make the comparison of battery is full.In the process, constant current charging ratio with a total capacity of the battery capacity, is called a constant current ratio.It is to measure a set of battery charging efficiency in the process of charging the key values.Usually shows that the greater the percentage in the constant current phase into the higher power, also it shows that the battery charging efficiency is higher.

Can be seen from the table, the ternary lithium battery and lithium iron phosphate battery charging below 10 c, constant current ratio has no obvious difference, more than 10 c ratio when charging, lithium iron phosphate batteries constant flow rate reduce rapidly, charging efficiency rapidly reduced.

Fourth, cycle life can be at ease

For a family car, and ternary material lithium iron phosphate power battery rated cycle life are far more than the actual user habits and so on the service life can be at ease completely.With BAK battery current high capacity battery 18650, for example, in the charge and discharge cycle after 1000, more than 90% of the battery capacity can still keep in the original.Because the author itself is the electric car owners, only the coldest winter of more than 1 months for the whole year, frequent charging when opening the warm wind to reach 2 days, the rest of the time the basic charge 3-4 days.Assume that charging to calculate an average of 3 days all the year round, need to use 1 year of about 6 times, cycle life about eight years to 1000 times after use, it also basic at present, more than the average consumer to change cycle.

Five, the safe enough material and process

Hardest part of the traditional internal combustion engine car is contains the huge energy of the fuel, ignition point or explosive of low liquid fuels like gasoline once leak is very easy to cause great potential safety hazard.Power battery and new energy vehicles, after complete battery management system (BMS) monitoring, each battery can get the most accurate control, preventing accidents

In 18650 battery products, for example.In monomer batteries craft, Bick choose configuration, respectively, in is the cathode protection additive and reactive additives, to prevent the electrolyte decomposition cause security problems.At the same time adding ceramic diaphragm and negative safety protection means such as ceramic coating, from the source control the produce of the accident.In addition, Bick small cylindrical 18650 battery group mode, keep enough safety distance between each battery, make sure that the single battery accident will not affect other batteries.

The ternary lithium batteries are dominant power battery market in the future

In the field of electric vehicles, Tesla in the United States has always been a measure of many domestic automakers.But with the strength of the traditional car companies develop new energy vehicles, BMW i3 launch has become a textbook example.It is interesting to note that both models have a ternary lithium battery as the power battery.In contrast, the domestic market, many car makers such as Jianghuai, BYD, Beijing also began its original use lithium iron phosphate battery models change ternary lithium battery.

Or that sentence: technology regardless of good or bad, only suitable or not suitable.Car companies at home and abroad for the battery type selected "consistent" is definitely not a coincidence.Believe in the near future, the batteries of electric cars market will reshuffle, ternary lithium batteries because of its low temperature resistance, high energy density, high charging efficiency good cycle life, and more features such as security, will also gain a foothold in new markets.

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