The difference between electric vehicle lead-acid battery and lithium battery

Lead-acid battery

Among them, lead - acid batteries for the largest number. Lead-acid batteries cost the least and are the most commonly used. China is the world's largest producer of lead-acid batteries. It contains less contaminated components and is recyclable. The disadvantage is that the volume is small. That is to say, under the same capacity, the battery is heavy and bulky. Current lead-acid batteries are basically developed from float-type batteries. The floating battery is not suitable for fast charging and high current discharge. Although the technician has spent a lot of effort to improve the product, it can be put into practical use, but its life is still very unsatisfactory.

Colloidal batteries are a developmental classification of lead-acid batteries. The simplest method is to add a gelling agent to the sulfuric acid to make the sulfuric acid electro-hydraulic into a colloidal state. A battery in which electro-hydraulic is colloidal is often referred to as a colloidal battery. Broadly speaking, the difference between a colloidal battery and a conventional lead-acid battery is not only that the electro-hydraulic is changed to gelatinous.

For example, non-solidified aqueous colloids are the same colloidal battery from the electrochemical classification structure and characteristics. Another example is the attachment of polymer materials in the grid, commonly known as ceramic grids, which can also be regarded as the application characteristics of gel batteries. Recently, the laboratory has added a targeting coupling agent to the plate formulation, which greatly improved the reaction utilization rate of the active material of the plate. According to non-public data, the energy ratio of 70wh/kg can be achieved. These are all examples of industrial practice and colloid battery application.

The difference between colloidal batteries and conventional lead-acid batteries is further developed from the initial understanding of electrolyte gelation to the electrochemical properties of electrolyte substrates and their application in grids and active materials. Its most important feature is: to produce a better battery along the 150-year-old lead-acid battery industrial road with a small industrial cost, the discharge curve is straight, the inflection point is high, and the specific energy is higher than the specific power. Conventional lead-acid batteries are more than 20% larger, and their lifespan is generally about twice as long as conventional lead-acid batteries. The high-temperature and low-temperature characteristics are much better.

Lithium-ion battery

The specific volume of a lithium-ion battery is better than that of a nickel-metal hydride battery. For a lead-acid battery of the same capacity, the weight of a lithium-ion battery is equivalent to a laptop, so that both old and weak women and women can use it. Its life can also be better than nickel-metal hydride batteries. The current mobile phone battery basically uses this battery. The internal resistance of the lithium battery is relatively large, and the use of the electric bicycle may cause the power of the vehicle to be insufficient when the battery is about to be completely discharged. The main problem of lithium-ion batteries is that the battery will explode in the state of over-charging and over-discharging. The cell phone batteries are all used in the battery, and then used with a good protection circuit to basically eliminate the problem of battery explosion. In the use of electric bicycles, it is necessary to use a series battery pack, and the protection circuit of the series battery pack is far more complicated than the protection circuit of the unit battery, and the material cost thereof is greatly increased. The current cost of a good lithium battery protection circuit is close to the price of the battery itself. Polymer lithium batteries have lower explosive lethality than lithium-ion batteries, but there is also the possibility of explosion and combustion. This is also the same as the lithium-ion battery needs to solve the problem.

The lead-acid battery process is simple and inexpensive, and the short-term charge and discharge life is short, average 300 times to 500 times of charge and discharge life, and the volume is heavy.

The same capacity of lithium battery is one of 5 parts of lead-acid weight, and the charge and discharge life is long: the number of charge and discharge of ternary polymer lithium is 1000 times, and the highest charge and discharge life of lithium iron phosphate is 2,000 times. Disadvantages: The price is high, so the penetration rate is less than that of lead and acid. 90% of electric vehicles and tricycles use lead-acid batteries.

Is lead-acid battery "real cheap" or "fake affordable"?

We must conduct a comparison to buy something, and have a comprehensive understanding of all aspects. The same is true for buying an electric car. For example, future maintenance, charge and discharge loss, battery replacement, etc. will cost a lot of money in the future!

It is understood that the average consumer's electric vehicle replacement cycle is around 4-5 years. Although lead-acid batteries are cheap, they have high annual losses and often need to be changed once a year. Generally speaking, the price of a better lead-acid battery is about 600 Yuan, so on the same electric vehicle it only costs about 2,400 Yuan to replace the battery.

Let's take a look at the electric car with a lithium battery. Buy a lithium battery electric car about 3,500 Yuan. The lithium battery warranty is about 3 years, which means that in the past three years, we don't have to pay extra to replace the battery. And the life of lithium batteries is very long, basically in about 5 years. In other words, as long as we usually cherish ourselves, we will not have any other expenses on the electric car in five years.

Therefore, such a contrast, on the surface, the electric car that bought the lead-acid battery was cheaper, in fact, this is a fake affordable.

Lithium batteries do not have memory. Don't pay too much attention when charging.

When charging an ordinary lead-acid battery electric vehicle, it has been worried about the memory effect of the battery. When a lithium battery is used, everyone can breathe a sigh of relief. The lithium battery does not have a memory effect, so it does not need to be too much in the daily charging process. Be careful!

Lithium batteries are less polluting than lead acid batteries.

Lithium batteries are greener than ordinary batteries, have little environmental pollution, and have a long service life to avoid environmental pollution caused by ordinary battery replacement.

Lithium batteries are lighter than bulky lead-acid batteries.

Lithium batteries are much smaller in volume and quality than lead-acid batteries. Under normal circumstances, lead-acid batteries have a weight of 16-30 kg and a large volume; while lithium batteries generally weigh 2.5-3.0 kg, and the volume is relatively large. Small, so riding is easy and easy to carry. General lithium battery electric vehicles are light and beautiful, easy to move, and many lithium battery electric vehicles can also be folded.

Lead-acid batteries are easy to explode? Lithium battery is safer and safer to use

Self-ignition explosions of electric vehicles often occur, most of which are caused by battery charging and discharging. Some experts have explained that the charging time of lead-acid batteries is too long. After charging to the end, after the two poles are converted into effective substances, if they continue to charge, a large amount will be generated hydrogen and oxygen gases. When the concentration of this mixed gas accounts for 4% in the air, it is too late to escape. If the vent hole is clogged or the gas is too much, an explosion will occur if it encounters an open flame, and the battery will be damaged if it is damaged, and the person will be injured or damaged. That is, once the lead-acid battery is overcharged, it will increase the chance of explosion. At present, lead-acid batteries on the market do not do any "overcharge protection", which makes the lead-acid batteries in charging, especially at the end of charging, extremely dangerous.

Now lithium batteries can circumvent this problem very well. The lithium-ion dog BMS battery management system can provide full protection for the battery. The functions include: charging/discharging high and low temperature protection; single-section overcharge/over-discharge voltage protection; charge/discharge over current protection; cell balance; short circuit protection; charge reminder and so on. First, we can try our best to extend the service life of the battery. Second, safety is more guaranteed.

The page contains the contents of the machine translation.