| 3.4. Battery Storage
3.4.1 General Storage
Conditions:
The battery should be stored under the following conditions.
(1) Low humidity
(2) 5 to 104oF(-15 to 40oC)
(3) Clean, and avoid direct sunlight.
3.4.2 Capacity after Long
Term Storage
After long term storage, all batteries deliver less than
rated capacity on first cycle. In cyclic application, full
capacity may be obtained through several charge/discharge
cycles, typically 2-3 cycles.
3.4.3 Refresh Charge
When batteries are placed in extended storage, it is recommended
that they receive a refresh charge at recommended intervals;
| Storage Ambient: |
Recommended Interval |
| Below
20 oC(68oF): |
12 months |
| 20 to 30oC(68
to 86oF): |
6 moths |
| 30 to 40oC(86
to 104oF): |
3 moths |
3.4.4 "Shelf Life"
- typical capacity vs. time
Self-discharge rate is very much dependent on the storage
temperature as shown in Figure 13.Lower temperatures allow
the battery to be stored for longer periods. (Each ten degree
centigrade drop results in a halving of self-discharge rate
and doubles storage time.)
3.4.5 "Shelf Life"
- storage time vs. temperature
Figure 14 shows the time for the capacity to decrease
to 50% of nominal capacity at each temperature during storage.
If the storage temperature is known, the graph may be used
for finding the most useful recommended refresh charge intervals.
3.4.6
Open Circuit Voltage and Residual Capacity
Residual
capacity can be estimated by measuring the open circuit
voltage as shown in Figure 15.
|
