>>>Rolls-Surrette 4 KS 21P

Rolls-Surrette 4 KS 21P


Rolls-Surrette 4 KS 21P deep-cycle 4V battery, 1104Ah/20h capacity, 3 + 7 years warranty (minimum order qty.)

SKU: SUR-183-118 Categories: , Tags: ,

Rolls Surrette has built a solid reputation over the years as one of the best, if not THE best, sources of deep-cycle batteries for renewable energy systems. Their batteries feature a high cycle life with thick, positive battery plates and a large liquid reserve. Surrette batteries are known for their unsurpassed reliability.

The 5000-series batteries are designed specifically for renewable energy applications, they are the longest-life batteries on the market, and come with a solid 10 year warranty, the longest in the industry. With good battery care many get 17 to 20 years of service out of these batteries. Our battery care instructions can help get the most out of your batteries.

The 5000-series batteries come standard with R-CAP recombiner vent caps (similar to “Water Miser” caps). These minimize water use, and cut down nearly 100% on the sulpheric ‘mist’ that batteries produce.

Adding batteries in series increases the Voltage, while keeping the Amp-hour size the same. Adding batteries in parallel keeps the Voltage the same, while increasing the Amp-hour size of the battery bank. For example, two S-550 batteries in series makes for a 12 Volt / 428 Ah battery bank. Adding another string of two S-550 batteries in parallel to these will increase the bank size to 12 Volt / 856 Ah.


Recommended Charge Settings (at 25C)

Charge State12 Volt24 Volt48 Volt
Bulk15.0 Volt30.0 Volt60.0 Volt
Absorb15.0 Volt30.0 Volt60.0 Volt
Float13.5 Volt27.0 Volt54.0 Volt
Equalize15.8 Volt31.6 Volt63.2 Volt
Temperature Compensation: -4mV/°C/cell


Equalize time: 2.5 hours, add distilled water as-needed halfway through

Absorb time: 0.42 x C / I, where C is the 20-hour battery bank capacity and I is the real-world charge current

For example, a 12 Volt bank of two S-550 batteries, 428Ah battery bank, with 1000 Watt in solar PV would have a realistic charge current of around 65 Amp in full sun. That makes for an absorb time of 0.42 x 428 / 65 = 2.76 hours = 2 hours 45 minutes

Maximum charge current: 15% of 20-hour battery bank capacity (ie. 0.15 x 428 = 65A for an S-550 battery for example), never more than 20%

Low-Voltage cut-off: 11.1 / 22.2 / 44.3 Volt (corresponds to about 80% Depth-Of-Discharge)



  • 4 Volt deep-cycle flooded lead-acid
  • 1104 Ah at 20 hours, 1557 Ah at 100 hours discharge rate
  • Double-wall container construction providing double protection from breakage and acid leakage
  • Cells can be replaced in-the-field, allowing the battery to be repaired in case a cell goes bad
  • Reliable and dependable, longest-life batteries on the market, designed for off-grid systems
  • Rolls 5000-series battery, Made in Canada!
  • Ten (10) years warranty: the first 36 months are full replacement, the next 84 months are prorated



Mnfr. model

Battery type

Battery Voltage

Amp-hours (20-hour)







There are no reviews yet.

Be the first to review “Rolls-Surrette 4 KS 21P”

Your email address will not be published. Required fields are marked *