Storage Characteristics; Storage Temperature; Storage Time; Storage Humidity - Invacare Robin Service Manual

1. Charge the battery until the LED turns green.
2. Remove the hand control from the charger.
3. Raise and lower the straps with a load for one minute.
4. Wait ten minutes.
5. Repeat Steps 3–4 until the battery is completely discharged.
Continue this process after the audible alert sounds and
the blue light flashes, indicating the battery is low.
6. Repeat Steps 1–5 two to three times.

4.2.1 Storage Characteristics

Essentially all rechargeable battery cells gradually discharge over time
whether they are used or not . This capacity loss is typically due
to slow parasitic reactions occurring within the cell . As such, the
loss rate (self- discharge rate) is a function of the cell chemistry and
the temperature environment experienced by the cell . Due to the
temperature sensitivity of the self-discharge reaction, relatively small
differences in storage temperature may result in large discharges
which are difficult or impossible to reverse. Cell and battery storage
issues of concern to most application designers relate either to the
speed with which the cells lose their capacity after being charged
or the ability of the cells to charge and discharge "normally" after
storage for some period of time. In both situations, general guidelines
developed for nickel-cadmium cells work acceptably for nickel-metal
hydride cells.
1586747-A

4.2.2 Storage Temperature

As already mentioned, the self-discharge reaction rate increases with
higher temperatures . Prolonged storage of the battery material
deteriorating faster; leakage performance will also deteriorate,
resulting in a reduced battery lifetime. It is recommended that, for
long storage, batteries should be kept at room temperature or below
(0-30°C or 32–86°F).

4.2.3 Storage Time

As the battery loses energy during storage, the voltage also drops. In
general, the battery capacity loss due to self-discharge during storage
can be recovered by recharging. If the battery is stored for over six
months, it is advisable to cycle the battery several times to resume
the battery capacity. Use good inventory practices (first in, first out )
to reduce time cells spend in storage.

4.2.4 Storage Humidity

Leakage and rusting of metal parts are accelerated in high
humidity environments, especially those with correspondingly high
Maintenance
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