Combine in parallel to get the required capacity, then series 4 banks together to give nominally 12V.
Ideal for Second/house battery and engine cranking.
 
SPECIFICATIONS
3.2V-180Ah
Voltage 3.2 V 
Nominal Capacity 180 Ah @ 0.3C
Weight Approx 5.7kg
Dimensions 180 x 71 x 279(H)mm
DC internal  resistance (max)     <1.0 mΩ 
Operating temperature 0°C to +45°C
Storage temperature -20°C to +55°C
SOC window 10% > 90%
Charge type CC/CV
Quick charge current 180A
Quick discharge current 360A
Standard discharge current 60A
Standard charge current 60A
Max operating discharge current 540A
Max pulse discharge current (<10s) 1800A
1000A Discharge capacity >90% capacity
Minimum Voltage 2.5V
Maximum Charge Voltage 3.65 V 
Life cycle @ 0.3C, 80% DOD, 2,000
Ceramic membrane technology.
Flame retardant housing.