LiFePO4 voltage systems: choosing a voltage class
LiFePO4 packs span from small 12V batteries to large industrial systems, and the voltage class is a system decision, not a battery decision. This guide explains how the classes relate and how to choose one.
Layered pack cross-section — the site's recurring diagram motif. It is a schematic, not a photograph of a product, factory or customer project, and it is not presented as a photograph of this company's factory.
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A LiFePO4 cell is about 3.2V nominal, so system voltages follow from the series count: four cells give 12.8V, eight give 25.6V, fifteen or sixteen give 48V to 51.2V, and larger counts give 72V-class and higher systems. The detail pages on this site illustrate the bottom of that ladder — a 12V 100Ah pack, a 12V 200Ah pack and a 12.8V 10Ah battery — while the wider range index includes 24V, 48V, 51.2V, 76.8V and other LiFePO4 configurations. A buyer should therefore think in voltage classes, not in single voltages: the class determines the inverter, the charger, the protection board and the wiring, and changing class later means changing all of them.
The 12V class suits small systems: RVs, camping, alarm systems, small solar systems and 12V equipment. Its advantages are familiar components, simple wiring and easy replacement. Its limit is current: at 12V, a given power needs a high current, so cables are thick and losses are higher. A 12V system delivering 1000W draws over 80A, which is a heavy cable and a heavy protection requirement for a small installation.
The 24V and 48V classes suit larger systems: home storage, larger solar systems, marine systems and light electric vehicles. At 48V, the same 1000W needs about 21A, so cables are thinner, losses are lower and the system scales more gracefully. The cost is complexity: more cells in series need balancing and management, the charger must match the higher voltage and the chemistry, and the protection board must be rated for the series count. The 48V guide on this site covers the 48V class in detail, including the 48V 15Ah pack example.
The 72V class and above suit industrial and traction uses: larger vehicles, industrial storage and equipment where power is high and cable runs are long. At those voltages, safety practice matters more — isolation, protection coordination and qualified installation — and the battery is one part of a designed system rather than a component to be chosen alone. A buyer moving to 72V-class systems should involve the system designer early, because the battery, the charger, the inverter and the protection must be specified together, and a battery ordered alone may not match any of them.
Choosing a class therefore starts from the system, not from the battery catalogue. What voltage does the inverter or motor controller accept? What power must the system deliver, and what current does that imply at each candidate voltage? What charger and protection options exist at that voltage? The class that answers all three questions with standard, available components is usually the right one, even when a neighbouring class looks cheaper per amp-hour.
Questions to ask before you order
- What voltage window does the inverter or controller accept?
- What current does the required power imply at each candidate voltage?
- What charger and protection options exist at that voltage class?
- Does the installation suit the pack's size and weight at that class?
- Is the system designed as a whole, or is the battery being chosen alone?
Related pages
LiFePO4 packs · 48V selection · 12V selection · 12V 200Ah pack
How to place an inquiry, step by step
- Send the device facts. Tell us the device type, the available space (length, width and maximum thickness), the nominal voltage you need, the capacity or runtime you target, and the peak current if your device has motors, radios or heaters.
- Name the model or the chemistry. If a page on this site matches, quote its model description and listing details. If nothing matches, say so and describe the chemistry and voltage you need, so the conversation starts on the custom route.
- Confirm documents and terms in writing. Ask for the certificate set for that exact model, confirm the minimum order, the price basis and the lead time for that listing, and confirm payment and warranty terms before you pay. Terms stated for one model listing do not transfer to another model.
- Agree the sample step. Confirm whether the next step is a listed sample, an engineering sample for a custom design, or a small trial order, and what test you will run on arrival — fit in the enclosure, runtime, or peak-current behaviour.
Send all of this in one message through the contact page: device type, space, voltage, capacity, peak current, model description if you have one, and the documents you need. That is the whole inquiry — no separate form, no account, no extra step.
What to send us now
Send one message with your device type, the space the pack must fit, the voltage and capacity you need, the peak current if it matters, and the model description if a page on this site already matches. Add the documents you need — certificates are available upon request — and whether you need a listed model or a custom design. Use the contact page or write to [email protected], or call +86-755-25629920. A specific message like that is what turns a range of hundreds of models into a short, answerable question.