5 Best APC UPS XS 1500 Replacement Battery (November 2026)

The best APC Back-UPS XS 1500 replacement batteries include the APC Power Saving Back-UPS XS 1500 BX1500G for a BX1500G-specific pack, the APCRBC124-UPC Replacement Battery for APC UPS BX1500M for BX1500M and broad model coverage, and the RBC7-UPC Replacement Battery Cartridge for Smart-UPS 1500VA for RBC7-compatible Smart-UPS models.

On this page (5 sections)

1. Which APC UPS XS 1500 replacement battery is the best fit?
2. How do you identify the right XS 1500 battery?
3. Is an assembled pack easier than separate batteries?
4. What is the difference between the APC model names?
5. Which replacement should you choose for your APC UPS XS 1500?

The best APC UPS XS 1500 replacement battery depends on the exact model number and connector. BX1500, BX1500G and BX1500M names can point to different fit requirements, so read the label on the back or bottom of your UPS before choosing a pack.

This roundup compares options by their stated compatibility and what comes assembled. The BX1500G-specific pack is the most direct choice for that model, while the RBC124-UPC lists both BX1500G and BX1500M.

The other picks target different APC or Smart-UPS models and need extra fit checks.

For broader battery basics, see our guide to best replacement UPS batteries 12V. A UPS provides backup power during an outage, and this explainer covers how a UPS battery backup switches to battery power.

Our picks at a glance

1. 1
   Best for a BX1500G-specific pack

   APC Power Saving Back-UPS XS 1500 BX1500G

   9.7/10 our score

   See it on Amazon
2. 2
   Best for BX1500M and broad model coverage

   APCRBC124-UPC Replacement Battery for APC UPS BX1500M

   9.5/10 our score

   See it on Amazon
3. 3
   Best for RBC7-compatible Smart-UPS models

   RBC7-UPC Replacement Battery Cartridge for Smart-UPS 1500VA

   9.4/10 our score

   See it on Amazon

4. 4

   Casil 12V 8Ah UPS Battery

   Best for a verified two-battery setup
   Check it
5. 5

   UPSBatteryCenter Compatible Replacement for APC Back-UPS XS

   Best for the original BX1500
   Check it

Which APC UPS XS 1500 replacement battery is the best fit?

The UPSBatteryCenter pack is the clearest match for a BX1500G, while the RBC124-UPC is the listed option here that explicitly covers both BX1500G and BX1500M. Verify the full model number before relying on any XS 1500 label.

We compared the stated model compatibility, pack format, connector details and warranty. Our score weighs specs, features and buyer feedback against what you’re shopping for.

A higher score here reflects a clearer match to the XS 1500 search, not a claim that every pack fits every XS model.

1

APC Power Saving Back-UPS XS 1500 BX1500G: Best for a BX1500G-specific pack

9.7/10Our score

• Compatible with BX1500G
• Assembled and ready to use
• Hot swappable
• 1-year warranty

This assembled pack is described for the BX1500G, making it the clearest fit when that exact model appears on your UPS label.

See it on Amazon

Pros

• BX1500G compatibility is named
• Arrives assembled
• Hot-swappable design

Cons

• The named compatibility is specific to BX1500G

For a UPS marked BX1500G, this assembled UPSBatteryCenter pack is the most direct match among these choices. Its compatibility information names BX1500G, and the pack arrives assembled and ready to use.

The pack is described as hot swappable, which can allow battery replacement without taking the UPS out of service when the unit and its instructions support that process. Follow APC’s instructions for your specific UPS before handling or replacing its battery.

The key limitation is the model match: this pack specifically names BX1500G. Don’t assume that the same pack fits a BX1500M or another XS 1500 variant because the family name looks similar.

Choose it when your label says BX1500G and you want a complete assembled pack. Compare the model number and connector with your manual before ordering.

2

APCRBC124-UPC Replacement Battery for APC UPS BX1500M: Best for BX1500M and broad model coverage

9.5/10Our score

• Replaces RBC124
• Compatible with BX1500M and BX1500G
• 24V sealed lead-acid pack
• 2-year warranty

This preassembled RBC124 replacement names both BX1500M and BX1500G among its compatible models. Confirm the full model suffix before choosing it.

See it on Amazon

Pros

• Names both BX1500M and BX1500G
• Preassembled kit with connectors and cables
• 2-year warranty

Cons

• Compatibility list includes several different UPS models

The APCRBC124-UPC is the broadest match here for shoppers whose UPS is labeled BX1500M or BX1500G. Its compatibility details name both models, along with several other Back-UPS and Smart-UPS units.

It is a preassembled 24V sealed lead-acid battery pack with new connectors, cables, fuses and a metal enclosure. UPC states that the pack carries a 2-year warranty.

It is made by Upgrade Parts Company, rather than APC.

Because the compatibility list spans multiple model families, use the full model number to confirm that RBC124 is the correct cartridge for your particular UPS. If the label shows a different suffix, check the manual or APC’s battery reference before buying.

This is the strongest option in this group when you need an RBC124 replacement and your model appears on its compatibility list. It is not a universal pack for every APC XS 1500.

3

RBC7-UPC Replacement Battery Cartridge for Smart-UPS 1500VA: Best for RBC7-compatible Smart-UPS models

9.4/10Our score

• 12V 18Ah sealed lead-acid battery
• Compatible with select Smart-UPS models
• Assembled cartridge
• 2-year warranty

This cartridge is aimed at RBC7-compatible Smart-UPS models such as SMT1500 and SUA1500, rather than the Back-UPS XS 1500 family.

See it on Amazon

Pros

• Compatibility names several Smart-UPS models
• Includes connectors, cables and fuses
• Assembled cartridge

Cons

• Not identified for BX1500G or BX1500M

The RBC7-UPC is aimed at RBC7-compatible Smart-UPS units, including models such as SMT1500 and SUA1500. It is not identified for the Back-UPS XS 1500 models BX1500G or BX1500M.

This assembled cartridge uses a 12V 18Ah sealed lead-acid battery and includes connectors, cables and fuses. UPC states a 2-year warranty, though its warranty description includes specific conditions for the original purchaser and battery state of charge.

The similar 1500VA naming can make this cartridge easy to confuse with a Back-UPS replacement. Check whether your UPS is a Smart-UPS model that takes RBC7 before considering it; the XS 1500 name alone does not indicate compatibility.

Choose this only when your unit’s exact model and cartridge reference match the RBC7 compatibility details. For the BX1500M-specific alternative, see our guide to the best APC BX1500M replacement battery.

4

Casil 12V 8Ah UPS Battery: Best for a verified two-battery setup

9.2/10Our score

• Two 12V 8Ah sealed lead-acid batteries
• AGM design
• F2 terminals
• 1-year prorated warranty

This two-battery set is described for several smaller APC models and RBC17 replacements. Use it for an XS 1500 only if your unit’s manual confirms the battery format and terminals.

See it on Amazon

Pros

• Two batteries in the pack
• Sealed AGM construction
• Terminal type is specified

Cons

• The stated model examples are smaller APC units

Casil’s two-pack contains two 12V 8Ah sealed AGM batteries with F2 terminals. Its named examples include smaller APC models such as BE550G, ES 650 and XS 1300VA, so it should not be treated as a ready-made XS 1500 pack.

Separate batteries may suit a UPS that uses individual batteries, but the voltage, capacity, terminal type, dimensions and wiring all need to match the unit’s instructions. A compatible voltage by itself does not confirm the right fit.

Casil describes the batteries as maintenance-free and gives a 1-year prorated warranty. Check the manual for the required battery arrangement and terminal type before buying a two-pack for any UPS.

For a smaller APC unit, compare the model-specific guide to the best APC BE600M1 replacement battery. This Casil set is a candidate only when the exact battery format is confirmed.

5

UPSBatteryCenter Compatible Replacement for APC Back-UPS XS: Best for the original BX1500

8.9/10Our score

• Compatible with BX1500
• Plug-and-play pack
• 2-pin connector
• 1-year replacement warranty

This replacement pack names BX1500 compatibility and a 2-pin connector. The model is not identified as BX1500G or BX1500M, so check the exact label before ordering.

See it on Amazon

Pros

• BX1500 compatibility is named
• Plug-and-play pack
• 1-year replacement warranty

Cons

• Exact suffix compatibility is not stated

This UPSBatteryCenter pack names the original BX1500 as its compatible model and specifies a 2-pin connector. It also describes a plug-and-play pack with a 1-year replacement warranty.

The compatibility detail does not specify BX1500G or BX1500M. That makes it a less certain match for those suffix models than the options that name them directly.

Check the back or bottom label and compare the connector with the pack before ordering. If your label includes a suffix, confirm that exact model with the manufacturer or UPS manual instead of assuming that “BX1500” covers it.

This pack is most relevant when the unit is labeled BX1500 without an added suffix. If you need a different cartridge, our guide to the best APC RBC17 replacement battery covers a separate battery family.

How do you identify the right XS 1500 battery?

Read the complete model number on the UPS label, then match it to a replacement pack’s compatibility details and connector. For a CyberPower CP1500AVRLCD3, see our replacement battery guide.

The phrase “XS 1500” by itself does not confirm that two packs are interchangeable.

Before ordering, check these details:

• Model suffix: distinguish BX1500, BX1500G and BX1500M.
• Battery reference: confirm whether the UPS manual names RBC124, RBC7 or another cartridge.
• Pack or battery format: determine whether the UPS takes an assembled pack or separate batteries.
• Connector and wiring: compare the connector shape and cable arrangement with the original pack and manual.
• Voltage and layout: use the battery arrangement specified for your UPS, not a guess based only on a 12V label.

A replacement cartridge can be easier to install when it arrives assembled, but it still has to match the UPS. If the model label is hard to read, photograph it and consult the manual before buying.

Is an assembled pack easier than separate batteries?

An assembled pack includes batteries and the connecting parts as a unit, while separate batteries need to match the original layout and terminals. That makes the pack style an important part of your fit check.

The BX1500G pack and RBC124-UPC are described as assembled kits. Casil’s 12V 8Ah option is a two-battery set, so it depends on the UPS using that battery format and terminal type.

Do not open or modify a battery pack unless the manufacturer’s instructions say to do so. Follow the UPS manual for shutdown, disconnection and installation steps, and recycle the old battery through an appropriate battery collection program.

What is the difference between the APC model names?

BX1500, BX1500G and BX1500M are distinct model identifiers, and a match for one should not be assumed to cover the others. The replacement choices here show why the suffix matters: one pack names BX1500G, another names BX1500M and BX1500G, and another only names BX1500.

The family name also differs from other APC battery references. RBC17 and RBC7 are separate cartridge families, so an XS 1500 search result that mentions another APC battery does not make it the right replacement.

If you’re comparing backup equipment as well as batteries, our explainer on the difference between a UPS and a battery backup explains the basic terms. For a replacement, the model label and manual remain the deciding references.

Which replacement should you choose for your APC UPS XS 1500?

Choose the BX1500G-specific pack if your label says BX1500G and you want an assembled replacement. Choose RBC124-UPC for a BX1500M or BX1500G only after confirming that RBC124 matches your unit.

For a unit labeled BX1500 without a suffix, the UPSBatteryCenter pack names that model and a 2-pin connector. Treat the RBC7 cartridge and Casil two-pack as options for their stated model or battery formats, not as default XS 1500 replacements.

Check the complete model number, cartridge reference and connector before you buy. That is the safest way to narrow down the best APC UPS XS 1500 replacement battery for your particular unit.

Our top 3 picks at a glance

1. 1
   Best for a BX1500G-specific pack

   APC Power Saving Back-UPS XS 1500 BX1500G

   9.7/10 our score

   See it on Amazon
2. 2
   Best for BX1500M and broad model coverage

   APCRBC124-UPC Replacement Battery for APC UPS BX1500M

   9.5/10 our score

   See it on Amazon
3. 3
   Best for RBC7-compatible Smart-UPS models

   RBC7-UPC Replacement Battery Cartridge for Smart-UPS 1500VA

   9.4/10 our score

   See it on Amazon

Frequently asked questions

Which battery fits an APC Back-UPS XS 1500?

The right replacement depends on the complete UPS model number, such as BX1500, BX1500G or BX1500M. Match that label against the battery pack’s compatibility details, then confirm the connector and pack layout in the UPS manual.

A shared “XS 1500” name alone is not enough to establish fit.

Can I use a BX1500G battery in a BX1500M?

Only use a pack whose compatibility details include your exact model. The BX1500G-specific pack here names BX1500G, while the RBC124 replacement names both BX1500G and BX1500M.

Check your UPS label and manual before ordering, since suffixes can distinguish different units.

Is RBC7 the same as RBC124?

No. These are different replacement cartridge names with different stated compatibility lists.

RBC124-UPC names BX1500M and BX1500G, while RBC7-UPC names Smart-UPS models such as SMT1500 and SUA1500.

Use the cartridge reference and full UPS model number to confirm the match.

Can I replace a UPS battery with separate 12V batteries?

Only if the UPS manual specifies that battery arrangement and the replacement batteries match its size, terminals and wiring. Some replacement packs arrive assembled with connectors and cables, while individual batteries require correct installation.

Disconnect power and follow the manufacturer’s safety instructions before handling a UPS battery.