Instruction/ maintenance manual of the product Ni-MH Duracell
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T T Ni-MH Rechargeable Batteries able of Contents 1 Introduction 2 General Characteristics 3 Composition and Chemistry 3.1 Active Components: Positive and Negative Electrodes 3.2 Electrolyte 3.3 Cell Reactions 4 Battery Construction 4 .1 Basic Cell Construction 4.
Ni-MH Rechargeable Batteries 1 1 2 2 Introduction Rapid advancements in electronic technology have expanded the number of battery-powered portable devices in recent years, stimulating consumer demand for higher -energy r echargeable batteries capable of delivering longer service between recharges or battery replacement.
Ni-MH Rechargeable Batteries 3 3 Composition and Chemistry A rechargeable battery is based on the principle that the charge /discharge pr ocess is reversible, that is, the energy delivered by the battery during dischar ge can be replaced or r estored by rechar ging.
The sealed nickel-metal hydride cell uses the “oxygen-recombination” mechanism to prevent a build- up of pressure that may r esult from the generation of oxygen towards the end of charge and overcharge .
4 Ni-MH Rechargeable Batteries 4 4 Battery Construction DURACELL standard-sized nickel-metal hydride batteries are constructed with cylindrical and prismatic nickel- metal hydride cells . DURACELL nickel-metal hydride batteries are a sealed construction designed for optimal perfor- mance and maximum safety .
Ni-MH Rechargeable Batteries The basic differences between the prismatic c ell and the cylindrical cell are the construction of the electrodes and the shape of the can. Prismatic cells are designed to meet the needs of compact equipment where space for the battery is limited.
Ni-MH Rechargeable Batteries 5.1 General Characteristics The discharge characteristics of the nickel-metal hydride cell are very similar to those of the nickel- cadmium cell. The charged open circuit voltage of both systems ranges from 1.25 to 1.35 volts per cell.
T ypically , when the current is higher and the temperature is lower , the operating voltage will be lower . This is due to the higher “IR” drop that occurs with increasing current and the cell’ s increas- ing resistance at the lower temperatures.
Figure 5.4.1 compares the gravimetric and volumetric energy density of nickel-metal hydride and nickel-cadmium cells. As indicated, nickel-metal hydride cells deliver more energy per weight or volume than nickel-cadmium cells.
Ni-MH Rechargeable Batteries 5.7 Internal Impedance DURACELL nickel-metal hydride batteries have low internal impedance because they are manufactured using cells designed with thin plate electrodes which offer large surface areas and good conductivity .
10 Ni-MH Rechargeable Batteries Although many years of premium performance can be enjoyed from a nickel-metal hydride battery that is properly handled, the capacity delivered in each charge/discharge cycle will eventually begin to decr ease.
6 6 Ni-MH Rechargeable Batteries 6.1 General Principles Recharging is the process of r eplacing energy that has been discharged from the battery . The subse- quent performance of the battery , as well as its overall life, is dependent on effective charging.
Duracell recommends the charge termination method described in Section 6.3.1. The voltage of the nickel-metal hydride battery during charge depends on a number of conditions, including charge current and temperatur e.
13 Ni-MH Rechargeable Batteries The following summary explains some of the recommended methods for charge contr ol. The charac- teristics of each of these methods are illustrated in Figure 6.2.1 . In many cases, several methods ar e employed, particularly for high rate charging.
6 . 2 . 5 Delta T emperature Cutoff ( ∆ TCO) 6 . 2 . 6 Rate of T emperature Increase (dT/dt) 6 . 3 Charging Methods Ni-MH Rechargeable Batteries This technique measures the battery tempera- ture rise above the starting temperature during char ging and terminates the charge when this rise exceeds a pre- determined value.
6. 3. 1 Duracell’ s Recommendation: Three-Step Charge Procedure 6. 3. 2 Low-Rate Charge ( ≈ 12 hours) 6. 3. 3 Quick Charge ( ≈ 4 hours) 6. 3. 4 Fast Charge ( ≈ 1 hour) Ni-MH Rechargeable Batte.
6. 3. 5 T rickle Charge 6 . 4 Thermal Devices 16 Ni-MH Rechargeable Batteries A number of applications require the use of batteries which are maintained in a fully-charged state. This is accomplished by trickle charging at a rate that will replace the loss in capacity due to self-dischar ge.
7 7 Cycle and Battery Life 7.1 Cycle Life The cycle life of nickel-metal hydride batteries depends on the many conditions to which the battery has been exposed, as is true for all types of recharge- able batteries.
7 . 2 Battery Life T able 7 . 2 .1 Recommended Permissible Low Rate Charge 15 ° C to 30 ° C (59 ° F to 86 ° F) 0 ° C to 45 ° C (32 ° F to 113 ° F) Quick Charge 10 ° C to 30 ° C (50 ° F to 8.
8 8 Safety Considerations Duracell’ s nickel-metal hydride batteries are designed to ensure maximum safety . Each cell includes a resealable pressur e relief mechanism (safety vent) to prevent excessive build-up of pressur e in the cell in the event it is overcharged excessively , exposed to extreme high temperatures, or otherwise abused.
20 Ni-MH Rechargeable Batteries T able 8 . 0 . 1 T est T est Conditions T est Results Flat Plate Crush T est Cell is crushed between No explosion, sparks, or flames. two flat surfaces. Impact T est A 20 lb. weight is dropped from No explosion, sparks, or flames.
Ni-MH Rechargeable Batteries 21 9 9 Proper Use and Handling Nickel-metal hydride batteries can give years of safe and reliable service if they ar e used in accordance with recommended procedur es and are not abused. The batteries can be used in any operating position.
22 Ni-MH Rechargeable Batteries 9 . 3 Waste Management: Recycling and Disposal 9 . 2 T ransportation Procedures for the transportation of batteries are specified by the United States Department of T ransportation in the “Code of Federal Regulations,” CFR49, entitled “T ransportation.
An important point after buying a device Duracell Ni-MH (or even before the purchase) is to read its user manual. We should do this for several simple reasons:
If you have not bought Duracell Ni-MH yet, this is a good time to familiarize yourself with the basic data on the product. First of all view first pages of the manual, you can find above. You should find there the most important technical data Duracell Ni-MH - thus you can check whether the hardware meets your expectations. When delving into next pages of the user manual, Duracell Ni-MH you will learn all the available features of the product, as well as information on its operation. The information that you get Duracell Ni-MH will certainly help you make a decision on the purchase.
If you already are a holder of Duracell Ni-MH, but have not read the manual yet, you should do it for the reasons described above. You will learn then if you properly used the available features, and whether you have not made any mistakes, which can shorten the lifetime Duracell Ni-MH.
However, one of the most important roles played by the user manual is to help in solving problems with Duracell Ni-MH. Almost always you will find there Troubleshooting, which are the most frequently occurring failures and malfunctions of the device Duracell Ni-MH along with tips on how to solve them. Even if you fail to solve the problem, the manual will show you a further procedure – contact to the customer service center or the nearest service center
