| Nominal Voltage |
51.2V nominal lithium battery |
16-series LiFePO4 configuration |
51.2V nominal; approximately 58.4V at full charge and approximately 40V–44.8V at the low-voltage cutoff, depending on BMS settings |
Confirm the chemistry, series count, charge voltage, discharge cutoff, and compatibility with the inverter or charger |
| Usable Capacity |
About 80% of the rated capacity is usable |
80%–90% usable capacity at the stated discharge rate |
Capacity is specified at a defined temperature, discharge current, and end-of-discharge voltage |
For a 100Ah battery: approximately 5.12kWh rated energy and 4.10–4.61kWh usable energy, depending on the allowed depth of discharge |
| Cycle Life |
Approximately 2,000–4,000 cycles |
At least 4,000 cycles at 80% depth of discharge |
Approximately 6,000–8,000 cycles under documented test conditions |
Check the test standard, depth of discharge, temperature, charge/discharge rate, and end-of-life capacity threshold, commonly 70% or 80% |
| Warranty |
3–5 years, often with conditions on cycle count or annual energy throughput |
5–8 years with a clearly stated minimum retained capacity |
8–10 years, with transparent exclusions, transfer terms, and a defined replacement or repair process |
Review the warranty start date, retained-capacity guarantee, cycle limit, labor coverage, shipping responsibility, and claim procedure |
| Safety Certifications and Testing |
UN 38.3 transport test documentation |
UN 38.3 plus IEC 62619 or an applicable national safety standard |
Relevant battery certification such as UL 1973; system certification such as UL 9540 where required; fire-propagation evaluation such as UL 9540A when applicable |
Request current test reports or certificates and confirm that they apply to the exact battery model, cell type, enclosure, and configuration |
| Battery Management System |
Overcharge, over-discharge, short-circuit, and temperature protection |
Protection functions plus cell balancing, state-of-charge monitoring, and event logging |
Independent cell monitoring, low-temperature charge protection, configurable limits, communication alarms, and firmware update capability |
Confirm continuous and peak current ratings, balancing method, temperature sensors, communication protocol, and fault-reset procedure |
| Continuous Discharge Current |
Approximately 50A–100A for a 100Ah battery |
Current rating matches the inverter’s continuous load with at least 20% headroom |
The manufacturer specifies continuous, peak, duration, ambient temperature, and parallel-connection limits |
A 5kW inverter can draw roughly 98A from a 51.2V battery before efficiency losses; verify the battery’s continuous rating accordingly |
| Indicative Hardware Cost |
Approximately US$180–US$300 per kWh |
Approximately US$250–US$400 per kWh for documented quality, protection, and support |
A higher purchase price is justified when it includes verified certifications, longer warranty coverage, monitoring, and local service |
Compare the same usable kWh, not only rated Ah; exclude or separately calculate freight, taxes, installation, cables, breakers, and communication hardware |
| Manufacturer Support |
Email-only support with no guaranteed response time |
Technical documentation, installation guidance, troubleshooting support, and response within 1–3 business days |
Regional service capability, trained installers, spare parts, remote diagnostics, firmware support, and a documented escalation process |
Ask for manuals, wiring diagrams, fault-code lists, service contacts, return instructions, and the expected replacement lead time |
| Communication Compatibility |
Basic dry contact or no external communication |
CAN or RS485 communication with a compatible inverter profile |
Published protocol, selectable inverter profiles, parallel-battery communication, and stable state-of-charge reporting |
Confirm connector type, pinout, baud rate, protocol, firmware version, and whether communication is required for warranty validity |
| Operating Conditions |
Discharge around 0°C–55°C; charging may be restricted below 0°C |
Defined charge and discharge temperature ranges with low-temperature protection |
Documented performance at the intended ambient range, with heating or thermal management where cold-weather charging is required |
Check humidity, altitude, enclosure rating, ventilation, mounting orientation, and cold-weather charging requirements |
| Total Cost of Ownership |
Lowest initial purchase price |
Balanced cost, usable capacity, warranty, safety documentation, and serviceability |
Lowest cost per delivered kWh over the expected service life, including installation, downtime, replacement, and recycling |
Use: total ownership cost ÷ lifetime delivered kWh; include efficiency losses, warranty limitations, maintenance, and end-of-life handling |
