Page 199 - Uninterruptible Power Supplies

Batteries
Batteries 197

Valve Rubber
Cap

Valve
Body

Gas Pressure

Figure 7.11 Vents.

Recharge Hours vs. Charging Voltage and Current
15 120
Charging Voltage
14 % Ah Returned 100
Charging Voltage and Current (Amperes) 10 9 8 7 6 5 Phase Current (Amperes) 80 % Ampere-hours Restored
13
12
11
Bulk
85% SOC
60

40
Absorption Phase

1 4 3 2 95% SOC Float Phase 20
0 0
0 5 10 15 20 25 30 35 40
Hours Recharge (13.8 Volts @ 0.1C)
Figure 7.12 Recharge hours versus voltage and current.

in the cycling regime. Some experimental reports are in favor, others
indicate an acceleration in hydrogen loss.
Recent developments have shown that short, high charging pulses
have a restorative effect on lead acid performance. Such pulses destroy
the build-up of sulphation on the plates. This ensures that the battery
returns to near its original performance figures. This treatment may be

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