| General |
| Brand |
Epoch Batteries |
| Model / SKU |
1250A-ES |
| Series |
Essential Series |
| Battery type |
Bluetooth deep-cycle LiFePO4 battery |
| Primary applications |
Kayak trolling motors, marine electronics, fish finders, small RV/van systems, portable solar, backup, and 12V auxiliary loads |
| Chemistry |
LiFePO4 / Lithium iron phosphate |
| Cell configuration |
4S LiFePO4 |
| Bluetooth monitoring |
Yes — free Epoch Pro app for compatible iOS and Android devices: state of charge, voltage, current, temperature, and BMS status |
| Bluetooth PIN |
If the app asks for one, it is printed on the battery label or in the product documentation |
| Internal heating |
No — this model is not self-heated |
| Cycle life |
4,000+ cycles |
| Warranty |
11-year manufacturer warranty; register within 90 days of purchase for full coverage |
| Voltage and capacity |
| Nominal voltage |
12.8V |
| Nominal capacity |
50Ah |
| Stored energy |
0.64kWh / 640Wh (nominal) |
| Runtime planning energy |
About 512Wh (80% of nominal) |
| Estimated runtime |
About 10.2 h at 50W, 5.1 h at 100W, 4.0 h at 10A (128W), 2.0 h at 250W, 1.0 h at 500W (DC loads at 25°C, new fully charged battery) |
| Operating voltage range |
10.0V – 14.6V |
| Maximum charge voltage |
14.6V |
| Current ratings |
| Max continuous discharge |
50A |
| Peak discharge |
170A for up to 3 seconds |
| Max continuous charge |
50A, all charging sources combined |
| Recommended charge current |
25A (0.5C, 50% of capacity) |
| Inverter sizing |
Inverter DC input current within 50A (about 640W at 12.8V); usable AC output is lower |
| Deep-cycle load warning |
Do not design continuous loads above the 50A per-battery continuous limit; 170A is a 3-second peak only |
| Series and parallel configuration |
| Series connections |
Max 4 batteries in series (24V, 36V, or 48V system classes) |
| Parallel connections |
Max 4 batteries in parallel |
| Maximum parallel capacity |
Up to 200Ah / 2.56kWh with four matched batteries in parallel |
| Maximum configuration |
4S4P (16 matched batteries): 51.2V nominal, 200Ah, 10.24kWh |
| Bank batteries |
Matched 1250A-ES batteries of the same age, condition, and state of charge; fully charge each before connecting it into a bank |
| Dimensions and weight |
| Length |
9 in (229 mm) |
| Width |
5⅝ in (143 mm) |
| Height |
8¼ in (210 mm) |
| Height with terminal bolts |
8⅝ in (219 mm) |
| Overall dimensions |
9 in L × 5⅝ in W × 8¼ in H (229 × 143 × 210 mm) |
| Footprint |
BCI Group 22NF |
| Weight |
14.3 lb / 6.5 kg |
| Case |
Compact Essential case |
| Mechanical and environmental |
| Enclosure protection |
IP54 per IEC 60529 |
| Weather resistance |
Dust protected and splash resistant; not waterproof or submersible |
| Terminal type |
Bolt terminals — use the supplied hardware and the torque on the product labeling |
| Mounting orientation |
Upright, unless Epoch documentation for this model allows otherwise |
| Charge temperature range |
0°C to 55°C / 32°F to 131°F |
| Discharge temperature range |
-20°C to 60°C / -4°F to 140°F |
| Recommended storage temperature |
0°C to 35°C / 32°F to 95°F, maximum 12 months |
| Long-term storage |
About 50% state of charge or higher, loads disconnected; check and recharge at least every 3 months |
| Self-heating |
No |
| Low-temperature charge protection |
Yes — the BMS blocks charging below 0°C / 32°F |
| Recommended charging settings |
| Charger type |
12V LiFePO4-compatible charger, converter, inverter charger, solar controller, or DC-to-DC charger |
| Compatible charger |
Epoch 12V 15A Lithium Battery Charger |
| Maximum continuous charge |
50A, all charging sources combined |
| Recommended charge current |
25A for one battery; 50% of bank capacity for multi-battery banks |
| Bulk / absorption voltage |
14.2V – 14.6V |
| Absorption time |
30 minutes per 200Ah of bank capacity |
| Float voltage |
13.4V – 13.8V; float disabled preferred where supported |
| Re-bulk voltage |
13.2V if programmable |
| Equalization |
Disabled |
| Temperature compensation |
0mV/°C (disabled) |
| BMS high-voltage cutoff |
14.6V |
| SOC recalibration voltage |
14.6V |
| Alternator charging |
DC-to-DC charger programmed for LiFePO4 |
| Protection and compliance |
| Battery management |
Built-in smart BMS |
| BMS protection |
Overcharge, over-discharge, over-current, short circuit, and high- and low-temperature disconnects |
| Overcurrent protection |
Install a fuse or DC-rated breaker as close as practical to the battery positive terminal |
| Compliance marks |
CE, RoHS |
| Transport |
UN 38.3 |
| Support |
US-based technical support |