CSB HR1221WF2 12V 5.1Ah Sealed Lead-Acid Battery

What is the CSB HR1221WF2?

The CSB HR1221WF2 is a 12 V, 5.1 Ah valve-regulated lead-acid (VRLA) battery with absorbent glass mat (AGM) construction from the CSB HR series (High Rate). It is sealed and maintenance-free: it never needs water.

CSB designs this series for high-rate UPS and float service standby power. A flame-retardant case is available on request.

What are the specifications of the CSB HR1221WF2?

Figures published by CSB in the HR1221W datasheet (2026 edition), with the CSB price list attributes marked:

Nominal voltage: 12 V
Nominal capacity (CSB price list): 5.1 Ah
Watts per cell, 15 minutes to 1.67 V/cell, 25 °C: 25 W
Maximum charge current: 2.1 A
Maximum discharge current: 90 A
Internal resistance: approx. 23 mΩ
Terminal: F2, Faston tab 0.250 in
Container: ABS, UL 94-HB; flame-retardant UL 94-V0 case available on request
Flame-retardant case: available on request (CSB price list)
Weight, approx.: 3.97 lb (1.8 kg)
Dimensions (L x W x H): 90 x 70 x 106.1 mm (3.54 x 2.76 x 4.18 in)
Case / group size (CSB price list): M5
Design life: up to 5 years in standby service at 25 °C; Eurobat (20 °C) classification: 3-5 years, standard commercial
Discharge temperature range: -15 to 50 °C
Float charging voltage: 13.5 – 13.8 V per battery at 25 °C (77 °F)
Equalize / cycle charging voltage: 14.4 – 15.0 V per battery at 25 °C (77 °F)
Standards (CSB datasheet): IEC 61056-1/2:2012, UL1973 Listed (MH66728) and UL1989 Recognized (MH14533)

How much power does the CSB HR1221WF2 deliver in a 15-minute discharge?

CSB’s constant-current table gives 12.5 A for 15 minutes to 1.67 V/cell at 25 °C, and the constant-power table gives 150 W per battery to the same end voltage. These are the figures to size a UPS or standby string against a 15-minute runtime.

How do I request a quote for the CSB HR1221WF2?

Request a quote by the part number HR1221WF2. Tell us the quantity you need and, where CSB lists more than one terminal or case option, which one. We confirm price, availability and lead time with the quote.