5 Best APC RBC17 Replacement Batteries (November 2026)

The best APC RBC17 replacement batteries include the APC Genuine UPS Replacement Battery RBC17 for a direct RBC17 match, the Mighty Max Battery 12V 9AH Replacement Battery for a battery-only replacement, and the APC Genuine UPS Replacement Battery RBC43 for select Smart-UPS models.

On this page (4 sections)

1. Which APC RBC17 replacement battery fits your UPS?
2. How we compared APC RBC17 battery replacements
3. What should you check before ordering an RBC17 replacement?
4. Which APC RBC17 replacement should you choose?

The best APC RBC17 replacement battery for a UPS that specifies RBC17 is APC's genuine RBC17 cartridge. It is the direct model match; the Mighty Max 12V 9Ah battery is a battery-only alternative for buyers who have confirmed the size, terminal and wiring fit.

RBC part numbers are not interchangeable just because they come from the same brand. Check the full UPS model number and the battery form before ordering, since the other assembled packs and batteries below are meant for different equipment.

Our picks at a glance

1. 1
   Best for a direct RBC17 match

   APC Genuine UPS Replacement Battery RBC17

   9.7/10 our score

   See it on Amazon
2. 2
   Best for a battery-only replacement

   Mighty Max Battery 12V 9AH Replacement Battery

   9.6/10 our score

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

   APC Genuine UPS Replacement Battery RBC43

   9.4/10 our score

   See it on Amazon

4. 4

   APCRBC157-UPC Replacement Battery for APC SMC1500-2UC

   Best for specified SMC and SMT models
   Check it
5. 5

   SigmasTek SP12-7.5

   Best for APC XS 1000 battery pairs
   Check it

Which APC RBC17 replacement battery fits your UPS?

The APC genuine RBC17 is the direct choice when your UPS model calls for that cartridge. The alternatives below are useful only when your specific UPS model and battery setup match their intended fit.

1

APC Genuine UPS Replacement Battery RBC17: Best for a direct RBC17 match

9.7/10Our score

• Genuine APC RBC17 cartridge
• Compatible with select APC Back-UPS models
• Fully assembled
• 2-year manufacturer warranty

The genuine cartridge is built for select APC models that specify RBC17. Confirm your exact UPS model before ordering.

See it on Amazon

Pros

• Model-specific compatibility
• Arrives fully assembled
• APC warranty

Cons

• Only for compatible APC models
• A new battery may not restore runtime if the UPS itself is failing

APC's genuine RBC17 is the clearest choice for an RBC17 replacement. APC lists compatibility with select Back-UPS models, including BE650G1, BR700G, BE850G2, BE850M2, BX850M and BN900M, but you should still confirm the exact UPS model before ordering.

The cartridge arrives fully assembled with replacement instructions. That can make the swap simpler than sourcing a battery and reusing parts, especially if you want the cartridge format intended for your UPS.

APC says its replacement battery cartridges are tested and certified for compatibility and backed by a 2-year manufacturer warranty. The battery is a rechargeable 12V lead-acid unit with a stated capacity of 5.5 amp-hours.

A new battery can restore runtime when battery wear is the problem. If the UPS itself is in poor condition, APC cautions that a battery change may not deliver the runtime you expect.

Choose this when your UPS specifies RBC17 and you want the direct APC cartridge. Confirm the model number on the UPS label, since nearby Back-UPS names can refer to different equipment.

2

Mighty Max Battery 12V 9AH Replacement Battery: Best for a battery-only replacement

9.6/10Our score

• 12V 9Ah sealed lead-acid battery
• AGM design
• F2 terminal
• One-year warranty

This battery is identified as compatible with RBC17, but it is a battery only. Check whether your UPS requires a harness or mounting parts.

See it on Amazon

Pros

• 12V 9Ah capacity
• F2 terminal
• One-year warranty

Cons

• No wire harness or mounting accessories included
• Dimensions and terminal must suit the existing setup

Mighty Max offers a 12V 9Ah sealed lead-acid battery identified as a replacement option for RBC17. It is a battery by itself, rather than a complete RBC17 cartridge, so check whether your UPS needs a wire harness or mounting parts.

Its dimensions are 5.94 x 2.56 x 4.02 inches, and it has an F2 terminal. Compare those details with the battery and connections currently in your UPS before deciding that it will fit.

The battery uses AGM construction and is rechargeable. Mighty Max includes a one-year warranty, but compatibility still depends on the UPS model and the way the battery connects inside it.

This is the alternative to consider if you can reuse the existing hardware and your UPS setup matches the dimensions and terminal. If you want a ready-to-install cartridge, the genuine APC RBC17 is the simpler match.

3

APC Genuine UPS Replacement Battery RBC43: Best for select Smart-UPS models

9.4/10Our score

• Genuine APC RBC43 cartridge
• For select APC Smart-UPS models
• Tested and certified by APC
• 2-year manufacturer warranty

RBC43 serves a different set of APC Smart-UPS models, so it is not an RBC17 substitute. Consider it only if your exact UPS model specifies RBC43.

See it on Amazon

Pros

• Genuine APC cartridge
• Model-specific Smart-UPS compatibility
• APC warranty

Cons

• Not an RBC17 cartridge
• Exact UPS model must match

The APC RBC43 is a genuine replacement cartridge for select Smart-UPS models, including SMT2200RM2UC, SMT2200RM2US, SMT3000RM2UC and SMT3000RMUS. It is not an RBC17 replacement, so only choose it when your own UPS model calls for RBC43.

APC says its RBC cartridges are tested and certified for compatibility. This unit is also backed by a 2-year manufacturer warranty, according to APC.

The important buying check is the exact model number. If your UPS uses an RBC17, the presence of another APC cartridge in this comparison does not make RBC43 a fit.

For other model-specific options, compare our best APC RBC48 replacement battery guide and best APC RBC7 replacement battery guide. Each cartridge serves its own compatible equipment.

4

APCRBC157-UPC Replacement Battery for APC SMC1500-2UC: Best for specified SMC and SMT models

9.1/10Our score

• For SMC1500-2UC and select SMT models
• Fully assembled pack
• Hot-swappable design
• 2-year UPC warranty

This assembled UPC pack targets specified APC Smart-UPS models, not RBC17 equipment. Match the battery pack to the UPS model number.

See it on Amazon

Pros

• Includes connectors and cables
• Pre-charged pack
• Hot-swappable design

Cons

• Not compatible as an RBC17 replacement
• For specified models only

The APCRBC157-UPC pack is designed for APC SMC1500-2UC, SMT1000RM2UC and SMT1000RMI2UC systems. Its 48V assembled format and included connectors make it a different kind of replacement from the 12V RBC17 options.

UPC says the pack is pre-charged, maintenance-free and hot-swappable. The company includes connectors, cables and fuses, with metal enclosures where applicable, and provides a 2-year warranty.

Those details matter only if your UPS is one of the supported models. This pack is not a substitute for an APC RBC17 cartridge, so do not use its Smart-UPS compatibility as a reason to order it for a Back-UPS.

5

SigmasTek SP12-7.5: Best for APC XS 1000 battery pairs

8.8/10Our score

• Set of 2 AGM batteries
• 12V 7.5Ah each
• For APC XS 1000 UPS
• One-year warranty

This two-battery set is described for the APC XS 1000 and uses existing hardware. It is not a cartridge for an RBC17-compatible UPS.

See it on Amazon

Pros

• Two batteries included
• AGM design
• Uses existing hardware

Cons

• For APC XS 1000, not RBC17 systems
• Confirm battery dimensions and terminals

SigmasTek's SP12-7.5 is a set of two 12V 7.5Ah AGM batteries described for the APC XS 1000 UPS. It is a pair of individual batteries rather than an RBC17 cartridge, so confirm the UPS model and existing battery layout before considering it.

The set is meant to use existing hardware and comes with a one-year warranty. Its stated battery dimensions are 5.95 x 2.56 x 3.7 inches, which can help you compare it with the batteries already in your UPS.

This is a narrow fit for buyers whose equipment is the APC XS 1000 and needs this two-battery format. It is not the right option for a UPS that specifies RBC17.

If your UPS uses another APC cartridge, the best APC BX1500M replacement battery guide covers a different model-specific battery search.

How we compared APC RBC17 battery replacements

We compared the products by their stated compatibility, replacement format, battery details and warranty. The score weighs specs, features and buyer feedback against what you're shopping for.

The APC RBC17 ranks first because it is the only product here identified as the genuine RBC17 cartridge for select Back-UPS models. Mighty Max ranks next as a battery-only alternative that is identified for RBC17 use, with the caveat that the harness and mounting accessories are not included.

The RBC43, APCRBC157-UPC and SigmasTek pair are included to make model differences clear. They serve other APC UPS models and should not be treated as compatible replacements for RBC17 equipment.

What should you check before ordering an RBC17 replacement?

Check the full UPS model number, the required RBC part number and the physical battery setup before ordering. A matching voltage by itself does not confirm that a battery will fit or connect correctly.

Confirm the UPS model and RBC number

Read the model label on the UPS, then compare it with the replacement's stated compatibility. APC identifies RBC17 for select Back-UPS models, while RBC43 is for different Smart-UPS models.

If your UPS documentation calls for RBC17, do not substitute another APC cartridge based on brand alone. Our guide to best replacement UPS batteries in 12V explains why voltage is only one part of matching a replacement.

Check cartridge versus battery-only format

A complete cartridge can include the parts needed for that UPS format. A battery-only replacement may require you to reuse a harness or mounting hardware, and the Mighty Max battery does not include those accessories.

Compare the old battery's dimensions and terminal type with any replacement battery. If you are unsure how the wiring or mounting works, use the UPS manual or a qualified repair provider rather than guessing.

Consider the UPS condition

A replacement battery addresses battery wear, not every UPS fault. If a new battery does not restore expected runtime, APC notes that the UPS itself may no longer be in good condition.

Use the manufacturer's instructions for shutdown, removal, installation and disposal. Keep the UPS model and battery part number handy if you need support.

Which APC RBC17 replacement should you choose?

Choose the APC Genuine RBC17 when the UPS model specifies RBC17 and you want the matched cartridge format. Consider the Mighty Max battery only when its dimensions, terminal and battery-only setup fit your existing hardware.

The RBC43, APCRBC157-UPC and SigmasTek picks are for other UPS models and battery arrangements. Confirm compatibility by exact model before buying, and use the relevant replacement guide if your UPS needs a different cartridge.

Our top 3 picks at a glance

1. 1
   Best for a direct RBC17 match

   APC Genuine UPS Replacement Battery RBC17

   9.7/10 our score

   See it on Amazon
2. 2
   Best for a battery-only replacement

   Mighty Max Battery 12V 9AH Replacement Battery

   9.6/10 our score

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

   APC Genuine UPS Replacement Battery RBC43

   9.4/10 our score

   See it on Amazon

Frequently asked questions

Which UPS models use an APC RBC17 battery?

APC identifies RBC17 compatibility with select Back-UPS models, including BE650G1, BR700G, BE850G2, BE850M2, BX850M and BN900M.

Check the label on your UPS and confirm its model in APC's compatibility information before buying. Similar model names do not guarantee that the same cartridge fits.

Can I use a 12V 9Ah battery instead of RBC17?

A 12V 9Ah battery may be an option if its dimensions, terminals and connections match your UPS. Mighty Max identifies its battery as compatible with RBC17, but it does not include a wire harness or mounting accessories.

Check what your existing setup requires before choosing a battery-only replacement.

Should I choose a cartridge or a bare battery?

Choose a complete cartridge when you want a model-specific assembly with the needed parts ready to install. A bare battery can suit a replacement where you can reuse the existing wiring and mounting parts.

Compare fit and connections first, then follow your UPS manual's battery replacement instructions.

Will a new battery fix short UPS runtime?

A new battery can fix many runtime problems if the UPS is still in good condition. APC notes that an aging or faulty UPS may still fail to deliver expected runtime after a battery change.

If the UPS continues to perform poorly, consider whether the unit itself needs replacement.