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Primary batteries,
particularly those made from lithium can deliver up to eight times
the watt-hour capacity of conventional rechargeable batteries.
However, new rechargeable batteries using lithium anode will also
have higher capacity than the conventional rechargeable batteries.
Although lower than those of the primary sources, they will
provide a choice between freedom from charging and longer shelf
life of the primary, or the potential cost saving with
rechargeable batteries.
Logistics of
primary batteries are simple as portable energy can be made
available at remote distribution points that are unmanned and have
no electricity. Disposal is easy because little toxic material is
used. However, because of one-time use, the cost of the primary
battery is about 30 times higher than that of rechargeable cells.
Primary batteries are also simple to store, as they require no
maintenance. Primary battery has a shelf life of 10 years. In
contrast, lithium-based batteries are good for 2-3 years only,
whether used or not. Cool storage at a 40% charge level prolongs
longevity. Nickel-based batteries are good for five years and
longer, but require priming to regain performance after long
storage.
Stocking of rechargeable batteries require
significant maintenance, keeping track of the battery's state of
health, cycle count and age. Due to high self-discharge,
nickel-based batteries exhibit a 10-20% self-discharge per month.
This compares with 5-10% for lithium and lead-based batteries.
Self-discharge increases at higher temperatures. For this reason,
secondary batteries are not an effective media for long-term
energy storage, and must be fed before each activity. Specific
maintenance procedures must be followed with each type of
chemistry, operational use and environmental conditions.
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