Lithium battery VS Lead acid
Lead acid battery
Lead acid battery (VRLA) is a kind of storage battery whose electrode is mainly made of lead and its oxide, and the electrolyte is sulfuric acid solution. Under the discharge state of lead-acid battery, the main component of positive electrode is lead dioxide, and the main component of negative electrode is lead sulfate. Under the charging state, the main component of positive and negative electrodes is lead sulfate. The nominal voltage of a single cell lead-acid battery is 2.0V, which can be discharged to 1.5V and charged to 2.4V; under stress In use, six single cell lead-acid batteries are often connected in series to form a nominal 12V lead-acid battery, as well as 24V, 36V, 48V, etc. Lead acid battery is mainly composed of tubular positive plate, negative plate, electrolyte, separator, battery tank, battery cover, pole, liquid injection cover, etc. its electrode is composed of lead and lead oxide, and the electrolyte is an aqueous solution of sulfuric acid.
Lithium batteries are composed of four materials: positive electrode, negative electrode, diaphragm and electrolyte. The positive electrode materials are generally some lithium rich layered compounds, At present, common commercial cathode materials mainly include lithium cobalt oxide (LiCoO2), lithium manganate (LiMn2O4), lithium iron phosphate (LiFePO4) and ternary materials (limnxco1-x-yniyo2), etc. the negative electrode material is mainly graphite. Graphene has extremely strong conductivity, ultra-high strength, high toughness, high thermal conductivity, etc. it is hoped that it can replace graphite as the negative electrode of battery, or be used in other key materials of lithium battery, in order to greatly improve the energy density and power density of lithium battery. From the current stage of technological development, graphene battery is still in its infancy No, graphite has a layered structure, which sets a gate for the insertion of lithium ions. It is not only the decisive factor for the lithium battery to have a charge discharge platform and high coulomb efficiency, but also one of the important factors for it to become the key material of lithium battery.
Compared with lead-acid batteries, lithium batteries have higher average voltage and higher energy density. In other words, lithium batteries with the same size have more capacity. In addition, lithium batteries are relatively lightweight, easy to carry, and have a much longer service life, but the price is more expensive. In addition, lithium batteries are more adaptable to high and low temperatures, less affected by temperature, and more green.
Comparison of electrochemical performance between lithium battery and lead-acid battery
1. Comparison of weight and energy density between lithium battery and lead-acid battery
At present, the energy density of lithium battery is generally 200 ~ 260wh / g, that of lead acid is generally 50 ~ 70wh / g, and the weight energy density of lithium battery is 3 ~ 5 times that of lead acid, which means that the capacity of lithium battery is three to five times stronger than that of lead-acid battery under the same weight. Therefore, lithium battery has absolute advantages in energy storage.
2. Comparison of volume energy density between lithium battery and lead-acid battery
Since the volume capacity density of lithium battery is usually about 1.5 times that of lead-acid battery, under the same capacity, lithium battery is about 30% smaller than lead-acid battery.
3. Comparison of service life cycle between lithium battery and lead-acid battery
At present, the most popular lithium battery materials are ternary lithium and iron lithium. For example, ternary lithium batteries typically have 1000 cycles, lithium iron phosphate batteries have more than 2000 cycles, and lead-acid batteries typically have 300-350 cycles. Then it shows that the service life of lithium battery is about 3-6 times that of lead-acid battery.
4. Price comparison between lithium battery and lead-acid battery
Lead acid batteries are now cheaper than lithium batteries, which cost about three times as much as lead-acid batteries. However, through the service life analysis, if the same cost is used, the service life of lithium battery is longer.
5. Comparison of lithium battery and lead-acid battery in environmental protection
Because lead-acid batteries have very serious pollution, it can cause environmental damage in the production process or discarding waste batteries. Therefore, from the perspective of environmental protection, it is necessary to limit the reinvestment of lead-acid batteries or the use of lead-acid batteries in some areas.