When the constant current into the discharge had finished charging the battery because the battery’s internal resistance voltage drop generated, so the Laptop battery voltage has increased rapidly (A). Since then, the battery began to accept the office , the battery voltage to a lower rate continues to rise. In this context (Beach AB), the electrochemical reaction to generate a certain amount of oxygen in the same time as the same rate of oxygen and the chemical combination of hydrogen, therefore, the battery temperature and internal gas pressure is very low.
Process of loading the battery, composed of oxygen from the oxygen is higher than when the battery internal pressure increases. * The normal pressure inside the battery is about 1 pound force / inch 2. Overload, the rate of charge, the battery internal pressure will soon be in place by the force of 100 pounds / inch 2 or more.
Examine a variety of ways to approach charging nickel-cadmium battery gas production is an important issue. Bubbles gathered at the plate surface of the plate will reduce the surface involved in chemical reactions and increase the resistance of the internal battery. Overload, batteries produce much gas, if not rapidly compounds, the internal pressure of the IBM ThinkPad T43 battery would be increased considerably, which would damage the battery. In addition, the pressure is too large, sealed batteries will open porosity, so that the oven electrolyte. If the electrolyte has continued to make holes through the oven, the viscous nature of the electrolyte increases, the transport of ions between the plates becomes difficult, thus increasing the internal resistance of the battery capacity decrease.
After some time (c), the electrolyte begins to produce air bubbles, these bubbles are gathered on the surface of the plate, so that the effective area of the lower plate, so increases the ‘internal impedance of the battery, the battery voltage began to rise rapidly. This is close to an appropriate electrical signal.
Sufficient power, the rechargeable battery in the battery current is not converted into energy storage, but in the positive potential of oxygen on board Ultra generated. Oxygen is due to the electrolyte resulting from electrolysis is not due to return to the cadmium hydroxide, cadmium generated. Potassium hydroxide and water in the composition of the electrolyte, hydrogen and oxygen ions in oxygen, water and free electrons, the reaction formula
4OH? ↑ O2 → 2 H2O +4 e? Although the oxygen in the electrolyte can quickly produce surface of the negative plate in the electrolyte in the composite, but significantly increased the temperature of the ，Dell Latitude X1 battery. In addition, since the charging current used to produce oxygen, thereby increasing the pressure inside the battery.
Because a large number of hydroxyl ions from that of a small cadmium hydroxide is easier to get out of oxygen, so sharp rise in temperature inside the battery so that battery voltage drops. Therefore, the peak battery voltage curve (point D).
Electrolyte, the generation of oxygen compounds is an exothermic reaction, the battery during overload (point E) and produce oxygen continuously, so that the temperature and pressure inside the battery increases. If you force the exhaust causes the electrolyte to reduce the battery capacity has dropped and damage the battery. If the gas can be quickly discharged, the battery will explode.
Using net low constant current charging, the batteries have a dendrite. These dendrites can spread through the partition between the plates. In the proliferation of more severe cases, the dendrites will be part or all of the short-circuit the hp 346970-001 battery.
Ni-MH battery charging characteristics and nickel-cadmium batteries is similar in both charging voltage, the temperature curve shown in Figure 1-2 and Figure 1-3. As can be seen, charge termination, nickel-cadmium battery voltage drop is much larger than the nickel-hydride batteries in metal. When the battery capacity will reach 80% capacity prior to the temperature nickel-cadmium battery rises slowly when the battery capacity reaches 90% after nickel cadmium batteries will soon rise in temperature before. When the battery is fully charged when the base, Ni-Cd / Ni-MH battery is basically the same rate of temperature increase.
Process and method for recharging the rechargeable battery charging process can generally be divided into pre-charge, fast charge, top-up trickle charge into four stages.
Term not used for long or a new battery, the top one on the use of fast-support, it will affect battery life. Thus, the battery should charge a small current load to meet certain conditions, this step is called pre-load.
Fast charge is to use the current pricing stronger, faster recovery of the VGP-BPS9A/B battery power. Fast-charge rate of 1C or, more generally, the fast charging time, the battery capacity and loading rate-determining, cheap polo.
To avoid overcharging, the charger uses a number of low load current. The normal charge nickel-cadmium batteries can accept the charge rate of C/10 or less, so the charging time to over 10 hours. The use of low load current, the battery does not produce too much gas, the battery temperature is too high. As long as the battery charger, receiving the low rate constant-current battery charger will be able to provide a very small net charge current. Rechargeable battery with low current, the heat generated within the battery can be dispersed naturally.
Trickle Charger main problem is charging too slow, for example, with a capacity of 1 Ah battery, using C/10 charge rate, charging time to over 10 hours. In addition, the battery re charge a fill rate is low, when there is a dendrite. In most loader drip, lack of feedback voltage or temperature and therefore can not guarantee that the VGP-BPS9/B battery is fully charged, immediately after the bifurcation charger.
Fast charge constant current charging and pulse charging points are two types of constant current load is a constant current to the load current, the pulse load is the first use of pulsed current to charge the battery. And then let the battery discharge and so on. Great battery pulse amplitude, width very narrow. Usually discharge pulse amplitude for pulse charging 3 times. Although the amplitude of the pulse discharge and battery capacity related, however, with the ratio of current amplitude load remained unchanged.
Loading process, nickel cadmium batteries reduced to nickel hydroxide, nickel hydroxide, cadmium hydroxide, cadmium restore. During this process, the bubbles generated, gathered at the plate on both sides, so it will reduce the effective area of the plate, so that the plate resistance increases. Since the effective area of smaller plates, the charge in the full time required to increase capacity.
Join pulse discharge, the bubble left the plate and with the negative plate composed of oxygen. This process reduces the depolarization of the internal pressure of the toshiba PA3191U-4BRS battery temperature and internal resistance. At the same time, most of the charge in the battery is converted into chemical energy rather than gas and heat.
Charge-pulse width of discharge must be chosen to provide the plate to restore the original crystalline structure, thus eliminating the memory effect. Using measures of depolarization of discharge, may improve the efficiency of charge and allows very rapid charging current.
The use of some fast-load only the right, after the end of fast charging, the battery is fully charged. To ensure the recharge to 100% of electricity, but also by adding up the loading process. Complete the charge rate is generally not exceed 0.3c. By completing the charging process, the temperature will continue to increase when the temperature exceeds the limit, the charger into the charge state of maintenance.
Store, nickel cadmium batteries will power the discharge rate of C/30 to C/50 reduced to compensate for battery self-discharge due to the loss of electricity to supplement the charge after the end loader runoff should be transferred automatically to the process of electricity. Trickle charge, also known as maintenance costs. According to the battery self-discharge characteristics of slow loading rates are generally low. While connected to the battery charger and the charger connected to power in maintaining the state of charge, the charger load an additional rate to the battery, it will give the battery is fully charged, the state’s total .