The comparison between lead-acid batteries and lithium batteries of electric vehicles

A, Introduction of the lithium battery

The lithium battery is a kind of lithium metal or lithium alloy anode materials, using water electrolyte solution of the battery. Lithium battery is found by GilbertN. Lewis as early as 1912. In the 1970 s, M.S.W hit TIngham began to study lithium ion batteries. Because the lithium chemistry is very lively, it makes lithium metal processing, storage and usage have very high demand on the environment. The lithium battery has not been applied for a long time.

Working principle of the lithium ion battery:

Lithium ion batteries are generally use lithium alloy metal oxide anode material, graphite as the cathode material, using non-aqueous electrolyte battery.

Charge on the anode reaction is: LiCoO2 = = Li (1 -) x CoO2 + XLi++ Xe - (electronic)

Charge on a negative response is: 6 c + XLi++ Xe - = LixC6

Rechargeable batteries overall reaction: LiCoO2 + 6 c = Li CoO2 + LixC6 (1 - x)

The anode

The anode materials: many optional battery anode materials, mainstream products with lithium iron phosphate. The positive materials of the different control:

The positive reaction: discharging lithium ion embedded, charging lithium ion embedded. Charging: LiFePO4 - Li1 - xFePO4 + xLi++ xe - discharging: Li1 - xFePO4 + xLi++ xe - > LiFePO4.

The cathode

Anode materials: use graphite more. A new study has found that titanate can be better materials.

The cathode reaction: discharging lithium ion embedded, rechargeable lithium ion embedded.

Charging: xLi++ xe - + 6 c - > LixC6

Discharge: LixC6 - xLi++ xe - + 6 c

Second, the lead-acid battery is introduced

Lead-acid battery (VRLA), is a kind of electrode is mainly composed of lead and its oxide, battery electrolyte is sulfuric acid solution. Lead-acid battery discharge condition, the positive main ingredients for lead dioxide, negative main ingredients to lead; Charging status, the main components are all lead sulfate is negative.

A single case of lead-acid battery nominal voltage is 2.0 V, can discharge to 1.5 V, can charge to 2.4 V.In the application, often together with six single lead-acid batteries of nominal is 12 v lead-acid battery. There are 24 v, 36 v, 48 v, etc.

Lead-acid battery main features

Security seal

In normal operation, the electrolyte will not leaking from the battery terminal or shell. There is no free acid

Special liquid partition keeps acid, no free acid inside the battery, so the battery can be placed in any position.

Frustrated system

After the battery internal pressure is beyond normal levels, VRLA batteries will blow off gas and automatically seals, guarantee no excess gas in the battery.

Simple maintenance

Due to the complex system makes the gas into water, in the process of using VRLA batteries don't need to add water.

The service life is long

Adopted the structure of lead calcium alloy corrosion resistant tailgate VRLA battery can be used floating 10-15 years.

Stable quality and high reliability

The use of advanced production technology and strict quality control system, the VRLA battery quality is stable, reliable in performance. Voltage, capacity and seal online 100% inspection.

Safety certification

All VRLA batteries have passed UL safety certification.

Three, lithium battery and lead acid battery difference contrast

As we know, general contrast energy storage products from the weight energy density, energy density, volume, price, service life of applicability, angles such as national policy to:

The weight energy density

Current lithium battery energy density is in commonly 200 ~ 200 wh/g, lead acid is in commonly 50 ~ 70 wh/g, then the weight energy density of lithium battery is lead-acid 3 ~ 5 times, this means that under the condition of same capacity, lead-acid battery is lithium battery of 3 ~ 5 times, so the energy storage device on the lightweight, lithium battery occupy absolute advantage.

The volume energy density

The volume of a lithium battery capacity density is usually around 1.5 times of lead-acid battery, so under the condition of same capacity, lithium battery about 30% smaller than the lead-acid battery volume.

Use cycle

At present more popular material system is three yuan and lithium iron, three yuan power type lithium battery cycles are usually in more than 1000 times, lithium iron phosphate batteries cycles in more than 2000 times, lead-acid battery cycles are usually only about 300 ~ 350 times, so the service life of the lithium battery around three to six times that of lead-acid batteries.

The price

On the price of lithium battery in a lead to expensive, is about three times the left and right sides, but the service life of the analysis, in the cost of the same and is still a lithium battery cycle longer.

applicability

Lithium batteries because security is lead-acid battery is a bit poor, so need to be in use all kinds of security prevention work, such as preventing external force or accident damages to the lithium battery, because it may cause fire or explosion. Now the temperature suitability of lithium-ion batteries is very good also, adaptability, and so on other lithium battery is also no less in lead-acid batteries.

Use occasions

Lead-acid battery: auto start, electric vehicle batteries,

Lithium battery: mobile phone, computer, electric tools, now also used for electric car batteries.

Internal material

Lead-acid battery positive and negative extremely lead oxide, metal lead, for the sulfuric acid electrolyte,

The positive and negative electrode of lithium battery are cobalt acid lithium/lithium/manganese acid lithium iron phosphate, graphite, organic electrolyte.

The page contains the contents of the machine translation.