Alpha Technologies AlphaCellTM SMU-C Series - Manual (Page 11)

11 745-680-B11-001, Rev. A
1.5 Temperature and Battery Life
High temperatures can harm the battery and reduce its lifespan. Battery life decreases by
50% per 15ºF (~ 9ºC) above the standard operating temperature of 77ºF (25ºC).
To minimize battery damage:
Use temperature compensated chargers. •
Never allow the battery's temperature to exceed +131ºF (+55°C). •
Make sure operating area is properly ventilated, so heat cannot accumulate. •
Provide at least 0.39" (10mm) of space between batteries to enhance convective cooling. •
Visit sites annually to check for shorted cells, improperly set voltages, filter cleaning on •
ventilation systems, etc.
1.6 Internal Resistance and Short-circuit Current
The internal resistance of the battery is affected by temperature and charge state. The
internal resistance is lowest when the battery is fully charged.
Table 1-2, Internal Resistance and Short Circuit Current at 77ºF (25ºC)
1.0 Introduction, continued
Type
Internal
Resistance
(m Ω)
Short Circuit
Current (A)
SMU-C6-4.5 22 273
SMU-C6-7 14 429
SMU-C6-12 10 600
SMU-C 12-4.5 35 343
SMU-C 12-7 20 600
SMU-C 12-12 16 750
SMU-C 12-14 16 750
SMU-C 12-18 14 857
SMU-C 12-26 12 1000
SMU-C 12-28 12 1000
SMU-C 12-30 12 1000
SMU-C 12-35 10 1200
SMU-C 12-40 9.5 1263
SMU-C 12-55 6.0 2000
SMU-C 12-65 6.0 2000
SMU-C 12-75 5.5 2182
SMU-C 12-90 5.2 2308
SMU-C 12-100 5.0 2400
SMU-C 12-120 4.5 2667
SMU-C 12-134 4.0 3000
SMU-C 12-150 4.0 3000
SMU-C 12-200 3.8 3158
A short circuit current will decrease the voltage of the battery to 0V, and damage the internal
components.
CAUTION!