The Satellite 305 uses a 10.8 to 14.4 V lithium-ion battery with a capacity in the 31 to 98 Wh range, depending on the exact configuration. Common matching part numbers include PA3817U-1BRS, PA3817U1BAS, and PA5023U-1BRS. Because the Satellite R line covers many builds, the safest approach is to read the PA-number printed on your current pack and match it directly. A replacement runs $58.99.

Match the part number printed on your existing battery, which is the most reliable method. Flip the laptop over, remove the pack, and look for a PA-number such as PA3819U-1BRS, PA5110U-1BRS, or PA5184U-1BRS on the label. You can also check your full model number (for example an R840 or R950 variant) against the compatibility list. With 63 distinct part numbers covering this series, matching the exact code prevents ordering a battery with the wrong voltage or form factor.

A Satellite R replacement battery costs $58.99. Pricing is consistent across this category, so whether you need a PA3817U-1BRS, PA5023U-1BRS, or PA5184U-1BRS, the price is the same. Focus your decision on matching the correct part number and voltage (10.8 to 14.4 V) for your specific model rather than hunting for price differences within the line.

Not always, even between similar-looking models. While some Satellite R packs share a physical form factor, voltage ranges from 10.8 to 14.4 V and capacity from 31 to 98 Wh, so a PA3817U-1BRS will not necessarily fit a model that calls for a PA5110U-1BRS. Two related models in this line can require different batteries entirely. Always confirm the PA-number on your current pack before assuming compatibility across sub-series or model years.

The main differences are voltage, capacity, cell count, and the specific part number. Across the Satellite R range, voltage spans 10.8 to 14.4 V and capacity spans about 31 to 98 Wh, with standard and extended packs available. A 13.3-inch model may carry a lower-capacity pack than a 15.6-inch desktop-replacement variant. Part numbers such as PA3819U-1BRS, PA5023U-1BRS, and PA5184U-1BRS reflect these differences, so matching the exact code is essential.

Look on the label of your current battery, where the PA-number is printed. Turn the laptop over, release the battery, and read codes like PA3817U-1BRS, PA3817U1BAS, or PA5110U-1BRS directly off the pack. The same number is sometimes listed in service documentation for your model. This part number is the most accurate way to match a replacement from the 63 part numbers in this category, since voltage and form factor vary by sub-series.

Yes, on most Satellite R models the battery is a removable pack you can swap without tools. Turn off the laptop, flip it over, release the latch, and slide the old pack out, then seat the replacement (for example a PA5023U-1BRS or PA5184U-1BRS) until it clicks. Confirm the new battery matches your voltage (10.8 to 14.4 V) and part number first. If your specific model uses an internal pack, you may need to remove the bottom panel.

Common signs include rapidly dropping charge, the laptop shutting down well before reaching zero, and the pack no longer holding a charge near its rated 31 to 98 Wh capacity. You may also notice the system running only when plugged in or charge stalling at a fixed percentage. If your runtime has fallen sharply compared to when the laptop was new, it is time to match your PA-number (such as PA3817U-1BRS) and install a fresh battery at $58.99.