48V 100Ah Server Rack LiFePO4 Battery | 5.12kWh 3U Module for Home Solar & UPS

3U Server Rack Module: Compact Rack Depth

A 3U-high rack module — the compact end of the rack range. Choose 3U when rack height is limited and you would rather add modules horizontally than move to a taller enclosure. It is rated IP20, so it belongs in an indoor cabinet or plant room rather than outdoors, and the Smart BMS reports over RS485/CAN.

Where This Format Fits

• Residential solar and UPS cabinets with limited rack height.
• Indoor plant rooms and equipment closets.
• UPS backup strings built from 5.12 kWh modules.
• Installations that scale by adding 3U modules.

The 48V 100Ah Server Rack LiFePO4 Battery | 5.12kWh 3U Module for Home Solar & UPS is engineered for residential solar & off-grid homeowners. Built with Grade A LiFePO4 cells and a smart BMS (Smart BMS, RS485/CAN), it delivers 5.12kWh of usable energy with more than 6000 cycles at 80% depth of discharge — a maintenance-free, factory-direct alternative to lead-acid.

48V 100Ah Server Rack LiFePO4 Battery | 5.12kWh 3U Module for Home Solar & UPS Specifications

48V 100Ah Server Rack LiFePO4 Battery | 5.12kWh 3U Module for Home Solar & UPS Applications

• Home solar self-consumption & backup
• 48V UPS and data-center backup
• Server-room and network cabinet power
• Modular rack battery banks up to 60kWh

Why Choose CMX Battery — Your LiFePO4 Solar Home Battery Manufacturer & OEM/ODM Partner

CMX Battery is a LiFePO4 battery manufacturer and OEM/ODM partner with 9+ years of experience serving residential solar & off-grid homeowners worldwide. We deliver factory-direct pricing, wholesale and bulk ordering, and flexible OEM/ODM customization (voltage, capacity, BMS, communication, and enclosure) with competitive MOQs and reliable global shipping.

Every solar home battery is built with Grade A LiFePO4 cells and certified to CE, UN38.3, IEC 62619, RoHS, and UL standards, backed by a 5–10 year warranty. Need volume pricing or a custom pack? Request a quote and our engineering team will respond within 24 hours.

Request a Quote

Get factory-direct pricing for the 48V 100Ah Server Rack LiFePO4 Battery | 5.12kWh 3U Module for Home Solar & UPS. Contact CMX Battery sales for wholesale, OEM/ODM, and bulk order quotes.

Related rack formats in the same family include the 48V 200Ah 4U rack module for taller cabinets that need roughly double the energy per unit, while lower-voltage strings can use the sibling 24V modules listed below.

Related models in this series

Other rack-mount and stacked modules in this series:

• 24V 200Ah Rack-Mount LiFePO4 Battery
• 24V 100Ah Rack-Mount LiFePO4 Battery Module

Related reading

Further reading:

• High-Performance 48V Lithium-Ion Batteries for Solar

What 5.12 kWh actually runs

Nameplate energy and usable energy are not the same number. At the 80% depth of discharge this module is rated for, a single pack releases about 4.1 kWh to the load before the BMS closes the discharge path. The table below converts that figure into runtime for loads you will recognise from a home or a small equipment room. Figures are steady-state and assume the inverter and wiring losses sit in the single digits.

For backup duty the arithmetic runs the other way: a rack holding four modules carries roughly 16.4 kWh of usable energy, which is what a 2 kW critical load draws in a little over eight hours.

How many 3U modules fit in a standard cabinet

A 3U module occupies 133 mm of vertical rack space, since one rack unit is 44.45 mm. Because the module is only three units tall, a standard 19-inch cabinet fills with capacity far faster than one built around taller enclosures. Leave the extremes of the stack free for cable management and airflow, and the practical numbers look like this:

That lines up with the modular rack banks up to 60 kWh this page refers to elsewhere: twelve 5.12 kWh modules in a 42U cabinet land at 61.4 kWh. The bank scales in 5.12 kWh steps, so you can install what the load needs today and add modules later without replacing the cabinet, the busbars or the inverter.

3U or 4U: choosing the rack height

Pick the 3U format when the cabinet is shallow or wall-mounted and you would rather add modules horizontally than move up a frame size. Pick a taller module when connection count, not height, is the constraint.

Sizing a 48V UPS string from modules

For a UPS or standby string the question is rarely total capacity — it is how long the load has to survive. Working from about 4.1 kWh usable per module at 80% depth of discharge:

A bridge, not full autonomy, is usually the goal: the string carries the load until a generator starts or the grid returns. Size the bank to the bridge you actually need and let the modular format handle the rest, because an extra module is a 3U addition rather than a new cabinet.

What 6000+ cycles at 80% DoD means in years

Cycle life is quoted at a defined depth of discharge, and 80% is the figure this module is rated at. Run the pack through one full cycle a day and 6000 cycles is roughly sixteen years of service. Cycle it twice a week and the same rating stretches across several decades. Both spans outlast the 5 to 10 year warranty that covers the product, which is why the warranty, and not the cycle count, is normally the binding constraint in a residential or light-commercial installation.

Deeper cycling wears a cell faster than shallow cycling, so a bank that routinely discharges to 80% will reach the end of its service life sooner than one that stops at 50%. Where the load profile allows it, capping the daily discharge and keeping a reserve has a measurable effect on how long the bank lasts.

LiFePO4 against lead-acid in rack and UPS duty

The alternative most rack installations are still measured against is flooded or sealed lead-acid. The chemistry difference shows up in four places that matter inside a cabinet:

The number that decides most projects is cost per delivered kilowatt-hour across the life of the bank, not the purchase price of one unit. A lead-acid string that can only be cycled to 50% needs roughly twice the nameplate capacity to do the work of one comparable lithium module, and it will be replaced several times over the period in which the lithium bank stays in service.

Charging and BMS communication in practice

The module follows the standard sixteen-cell series LiFePO4 charge profile: a constant-current phase followed by a constant-voltage phase in the region of 57.6 V to 58.4 V, then a float or standby voltage below that. Confirm the final values against the datasheet supplied with your order before configuring a charger, because published profiles differ slightly between BMS revisions and the pack’s own limits always take precedence over a generic figure.

The smart BMS carries both RS485 and CAN, which means two things on site:

• A CAN connection to a hybrid or off-grid inverter lets the inverter read state of charge, voltage and current directly instead of inferring them from a voltage curve, which is what keeps the displayed percentage honest under load.
• An RS485 connection feeds a monitoring gateway, an energy management system, or a laptop running the commissioning tool, which is how most setup and firmware work is done.

Set the protocol on the BMS before energising the string, and match the inverter’s battery profile to the pack rather than leaving it on a lead-acid profile. A mismatched profile is the single most common reason a new bank reports the wrong state of charge on its first day in service.

Installation and commissioning checklist

• Confirm the cabinet is rated for the loaded weight and is anchored; a tall cabinet full of modules is heavy and top-heavy cabinets tip.
• Mount modules from the bottom up so the rack stays stable while you build it.
• Keep busbar runs short and equal in length across parallel modules so current shares evenly.
• Torque every terminal to the figure in the datasheet, then re-check after the first discharge cycle.
• Leave the top and bottom units of the stack clear for airflow; IP20 modules rely on the cabinet for ventilation.
• Set the BMS protocol and address before energising, because addresses are easier to change with the string cold.
• Record the first full charge and discharge and keep the numbers as the baseline for the bank.

Every cabinet is different and the module is rated IP20, so airflow and spacing are the installer’s responsibility rather than the pack’s. Where a cabinet is shared with other heat-producing equipment, size the clearance for the worst case rather than the average.

Safety, transport and certification

Four certification marks appear on this module and each answers a different question:

Certificates are issued against a specific build and BMS revision, so if a project needs the paperwork before a purchase order is raised, ask for the documents that match the configuration you intend to buy rather than a generic set.

OEM and private-label options

Because the module is built in our own plant, the specification can be adjusted rather than only relabelled. Typical changes for OEM and private-label orders include:

• BMS protocol maps matched to a specific inverter or EMS vendor.
• Enclosure branding, front-panel silkscreen and label artwork.
• Communication options: CAN, RS485, or both, with or without a Bluetooth module.
• Cabinet-level packaging, busbar kits and rack accessories supplied with the units.

A custom build changes the certification scope, so the paperwork is re-issued against the final configuration. Tell us which inverter you are pairing with and the volume you expect, and we will confirm what can be adjusted without disturbing the certification path.

Ordering, MOQ and lead time

Units ship as individual 3U modules, in rack-ready bundles, or as a complete populated cabinet, depending on the project. Minimum order quantities and lead times depend on the configuration, the certification paperwork you need and the destination, and both are confirmed at quotation along with the datasheet for the exact build.

Send your cabinet height, inverter model and target bank size and our engineers will return a layout, a protocol check and a quote. For projects already in procurement, tell us the delivery window and we will confirm what is achievable before you commit.

Frequently asked questions

Is the 3U module a drop-in replacement for a lead-acid bank?

Not in the mechanical sense, because a 3U rack module goes into a 19-inch cabinet rather than into the footprint of a set of lead-acid blocks. Electrically it is a 48V-class LiFePO4 battery, so an inverter or charger expecting a 48V nominal string will see a compatible voltage, but the charger profile has to be changed to LiFePO4.

Can I mix 3U and 4U modules in one bank?

Rack height is a mechanical question and the two formats belong to the same electrical family, but parallel units should match in age, capacity and BMS revision. Mixing formats in one string is a question for our engineering team rather than a decision to make on site.

Does the pack need ventilation in the cabinet?

Yes. The module is rated IP20, which means it is protected against solid objects but not against dust or water ingress, and it relies on the cabinet for airflow. Leave the top and bottom of the stack clear and avoid sharing a sealed enclosure with heat-producing equipment.

What depth of discharge should I run day to day?

The module is rated for 6000+ cycles at 80% depth of discharge. Shallower daily cycling generally extends service life, so where the load profile allows a reserve to be kept, keep it.

How does the inverter know the state of charge?

Over CAN or RS485, depending on the inverter. When the protocol is matched, the inverter reads state of charge, voltage and current from the BMS instead of estimating them from a voltage curve, which is far more accurate under load.

Can the bank grow later?

Yes, and that is the point of the format. Capacity is added in 5.12 kWh steps by fitting another 3U module, provided the cabinet, busbars and inverter can take the additional current.

Is the module suitable for outdoor use?

No. IP20 is an indoor rating. Outdoor and marine installations need an enclosure rated for the environment, and our IP65 and IP67 packs are built for those applications.

What certifications come with it?

The module carries UN38.3, IEC 62619, CE and RoHS. Certificates are issued against a specific build, so ask for the documents that match your configuration before raising a purchase order.

What is the warranty?

Coverage runs from 5 to 10 years depending on the configuration and the terms agreed at order, and the warranty terms are confirmed in writing with the quotation.

Do you sell to installers and system integrators as well as end users?

Yes. A large share of our volume goes to installers, integrators and distributors who buy in rack quantities, and volume pricing, OEM/ODM and private-label terms are all available. Tell us about the project and the annual volume.

How is the pack shipped?

Lithium batteries move under UN38.3 test reports and the transport documentation the carrier requires. The shipping method and the paperwork are confirmed with the order for the destination.

How do I get a quote?

Send the cabinet height, inverter model and target bank size through the form below or to sales@cmxbattery.com. Our engineers confirm the protocol match and return a layout and a quote.

Also Known As

This pack is the same hardware sold under several equivalent labels: 51.2V 100Ah
(16-cell series nominal voltage), 48V 100Ah (the 48V system-voltage convention used by most
inverters and chargers) and 5.12 kWh / 5120Wh (the same pack expressed as energy).
This page covers the 3U rack format of the module.

Compatibility & Communication

The Smart BMS communicates over RS485 and CAN and integrates with most 48V-class hybrid and off-grid inverters, as well as UPS strings that accept a 48V LiFePO4 bank.

Compatibility is listed for communication-protocol matching only. It is not an endorsement or a
certified-partnership claim. Send us your inverter or charger model and we will verify protocol
matching before shipment.

Rack Layout & Volume Pricing

Send us your cabinet depth, inverter model and annual volume — our engineers will confirm protocol matching and return a quote with the downloadable datasheet. Prefer email? sales@cmxbattery.com.