Lithium battery charge and discharge principles
In fact, lithium-ion battery is a lithium battery that came years ago is an alternative product to the anode reservoir used to suck carbon lithium-ion, discharge, lithium in lithium-ion Laptop battery from the anode, lithium reach-ion battery cathode. Lithium ion moves between the anode and cathode do not change the electrode itself. This is the lithium-ion batteries or lithium metal batteries is largely the difference. Lithium-ion battery anode graphite crystal, the cathode usually lithium carbon dioxide. Laden, the cathode of lithium atoms in the lithium-ion and electron ionization and the lithium ions to the anode movement and electronic synthesis of lithium atoms. Discharge for the lithium atoms from the graphite-anode surface of the crystal in a lithium-ion and electron ionization and the synthesis of lithium atoms at the cathode. Consequently, in the lithium batteries are only in the form of lithium-ion seems it is not the form of lithium metal, so that this cell is called a lithium-ion battery.
1, lithium-ion battery charge and discharge characteristics of
500MAH of aa-type lithium-ion battery charge and discharge curves. Single lithium-ion sony VGP-BPS2A battery charging voltage is best kept at 4.1 V 50 mV, charge current is typically look to 1c limit (500mA), otherwise it will result in permanent damage to lithium-ion batteries. Lithium-ion batteries commonly used constant current / constant voltage charging mode that is first use of 1c constant current charging the battery voltage rises when up to 4.1V if the charger should immediately at a constant voltage mode (4.1 V 50 mV), charging current gradually transferred if the battery is fully charged, charging current to the current trickle. This method can for about two hours battery (500mAh) is sufficient. Lithium-ion battery discharge current shall be not more than 3 c (1.5a), single-battery voltage must not fall below 2.2 V, as is otherwise cause damage. With the 0.2c to discharge current, battery voltage to 2.7V, you rated battery capacity (500mAh) emit 1c using the discharge current, the battery will emit 90% of battery capacity, while the temperature of the battery discharge capacity is also an effect, it offers a lithium-ion battery discharge when the temperature -20 ℃ ~ 60 ℃. A characteristic of lithium-ion battery is relatively easy to remaining capacity than lithium-ion battery voltage slowly decreased to show the passage of time, lithium-ion battery from discharging voltage of 4.1 V (4.2 V), discharge end voltage of 2.5V.
Second, the advantages and disadvantages of lithium-ion battery
Advantages: 1 Operating voltage is high; 2nd Small size, lightweight, energy is high, 3 Long life; 4 Safe and fast charge; 5th Provides a wide temperature range; 6th Discharge current is small, no memory effect, no pollution.
Disadvantages: 1 with the dry not interchangeable; 2nd Can not fast charge, 3 Internal impedance is high; 4 Voltage change significantly; 5th Discharge rate of large, rapid decline in capacity is not high-current discharge.
3, Li-Ion Battery Charger
Here is a new type of lithium-ion sony VGP-BPS2 battery charger module ps1719, it uses the constant current / constant voltage control of lithium-ion battery charger. Constant current, constant voltage adjusts easily to reduce the charge current to maximum current (constant current) 15% of the tax base is to be stopped from discrimination and the full load. There is also charging and full indicator. Ps1719-module voltage 9V, internal structure.
GND (①, ⑩ m) for the input, the output voltage grounding.
BATT-() ② feet, then the Dell Inspiron 1525 battery negative and ground access to the current control feedback resistance.
LED (⑥ m) for the collection status indicator pins. Maximum for the charge as filled with low-level display. Able to drive or inhaled current 3mA, may LEDs.
BATT + (⑦ meters), then the battery positive.
GAP (⑧ pin) outside interference capacitor anode. Capacitor positive pin (Vo), the capacity of not less than 0.22μF. ⑧ When the positive pulse input pin, it can reach to the pulse trickle charge mode.
RV (⑨ m) for the voltage feedback control input pin. Voltage-controlled equilibrium, the pin-for-BATT voltage of 2.5 V.
DRV (foot) for dead-zone voltage (0 ~ 3V) control driver OC output pin. Can absorb 30mA, driven PNP type power transistor to control the voltage, current.
Vo (pin) to about 4 V regulator output pin (charging a lithium-ion batteries), external anti-interference capacitor anode.
V + (pin) module, power supply positive voltage input pins need 6V ≤ V + ≤ 7V.
Application circuit PS1719 devoted to 3.6V Li-Ion battery can be used batteries for the three nickel-cadmium or nickel-metal hydride, module.
