Battery Knowledge of Foldable Ebikes

In the foldable ebike market, lead-acid maintenance-free batteries are most commonly used, batteries using glass fiber separator adsorption technology, and gel batteries using gel electrolyte technology.

Ⅰ. Lead-acid batteries for foldable ebike

The working principle of the light folding e bike lead-acid battery is that the anode and cathode of the lead-acid battery are immersed in the electrolyte, and 2V electricity is generated between the two electrodes. The chemical change in the discharge is that dilute sulfuric acid will react with the active materials on the positive and negative plates to form a new compound lead sulfate. The sulfuric acid component is released from the electrolyte by discharge, and the longer the discharge time, the lower the concentration of sulfuric acid. The consumed component is proportional to the discharge capacity. As long as the concentration of sulfuric acid in the electrolyte is measured, that is, the specific gravity, discharge capacity or remaining power can be known.

The chemical change during charging is that the lead sulfate produced on the positive and negative plates during discharging will be decomposed and reduced to sulfuric acid, lead and lead peroxide during charging, so the concentration of electrolyte in the battery gradually increases, that is, the specific gravity of the electrolyte increases. Gradually return to the concentration before discharge. This change indicates that the active material in the battery has been restored to a state where it can be powered again. When the lead sulfate of the two poles is reduced to the original active material, it is equal to the end of charging, the positive electrode plate produces hydrogen gas, and the negative electrode plate produces oxygen gas. In the final stage of charging, almost all of the current is used to electrolyze water, so the electrolyte will decrease.

Ⅱ. Lightweight foldable lithium-ion battery for electric bicycle

The working principle of a foldable electric bicycle lithium-ion battery is: when the battery is charged, the lithium in the positive electrode material is taken out, passes through the diaphragm and enters the negative electrode graphite. When the battery is discharged, the lithium ions are extracted from the negative electrode graphite and enter the positive electrode through the diaphragm Material. With the progress of charging and discharging, lithium ions are continuously inserted and extracted from the positive and negative electrodes.

Lithium ion battery is a kind of secondary battery. Due to its high energy density, large charge and discharge current, no memory effect, low raw material cost, environmental protection and many other advantages, its sales volume has grown rapidly year by year, and it will surely become a secondary battery in the future. The winner of the secondary battery. Since the 1990s, button batteries in electronic products, lithium batteries in mobile phones, and DC digital products have also begun to be applied to folding electric bicycles. However, the cost of lithium-ion batteries accounts for one-third to one-half of the cost of electric vehicles, which is far greater than the proportion of lead-acid batteries in the entire vehicle. And because lithium batteries have high specific energy and poor material stability, lithium batteries are prone to safety problems. With the development of technology, mature lithium-ion batteries will become the development trend of high-quality electric vehicles.