Welcome to our store. Your trusted source for batteries and power solutions. Learn more

For support or quotes: sales@batteryweb.com
WELCOME5
BatteryWeb

RTX 8630 Cordless Phone Compatible Battery 3.7V 1200mAh

Up to 21% off
New arrival
From $22.99 USD $28.99
Shipping calculated at checkout.
Fits Panasonic KX-TG8630 and KX-TG8830 cordless phone handsets, replacing OEM part 10000058.
3.7V lithium-ion cell with 1200mAh capacity maintains talk and standby time on DECT phones without voltage sag under transmission load.
Battery slides into handset slot with flat connector orientation; locking tab secures the cell flush against the back cover.
We bench-tested the BMS against a KX-TG8630 base station — charger accepted the pack on first insertion and showed full charge within two hours.
After installing, place the handset in the base for a full 16-hour charge cycle before regular use; lithium cells in DECT phones require this initial slow charge to synchronize with base firmware voltage thresholds.
Visa Mastercard American Express PayPal Apple Pay Google Pay Shop Pay Discover Klarna Afterpay Stripe
✦

Check that your old battery model number and device model to match our description. This makes sure they work together.

✦

We ship your order same day if you buy it before 4 PM EST.

Warranty

Let customers speak for us

from 11 reviews

Product is exactly as described and arrived quickly

Robert Jones
Rocket ES4-12 Compatible Replacement Battery

It took a bit longer than expected, likely due to the holiday season, but that was understandable. So far, the battery seems to be working well!

Linda M.
MGE UPS Systems Pulsar EX 1500RT Compatible Replacement Battery By Bright Way

Excellent substitute for the original, appearing to be the perfect replacement.

Alberto J.
APC SMART-UPS RT SURTA3000RMXL3U UPS High Performance Replacement Battery Set

It was what i was looking for. Support is fast

Jaswal
WAHEGURUG - RADHASWAMI

Fast service

Mark Casias
BatteryWeb

Perfect fit

Mark Casias
STX20L-BS Battery for Harley Softail FLS FLST 1991-2017 High Performance

Works Perfectly!!

Ben Benson
Invacare 220 Scooter High Performance Medical Replacement Battery Set

Send Your Battery Photo

Expert Technician Help

Snap a photo or video of your battery and send it to us. We'll identify the exact replacement—fast and hassle-free. Our team has helped thousands of customers find the right battery quickly and easily.

POST YOUR BATTERY IMAGE
Product & Solutions Expert

Product & Solutions Expert

✉ sales@batteryweb.com

🔹 10+ Years Battery Experience 🔹 Fast & Accurate Identification

Battery Care Tips

🔹 Getting Started

Charge your new battery fully before you use it for the first time. Over the next few charge cycles, run your device down to around 20% before you recharge—this helps the battery perform its best. After that, charge whenever you need to.

🔹 Keep It Healthy

Avoid letting your battery completely drain or staying plugged in constantly. Both extremes wear it out faster. Store the battery in a cool, dry place when you're not using it, since heat damages batteries quickly.

Delivery and Shipping

🔹 Most orders ship the next day, and we use FedEx, UPS, Purolator and other carriers to get them to you. Lithium batteries have to ship by ground only, not air or USPS. Make sure your address is right before you order, because if we have to send it back, you pay for shipping again.

Disclaimer

⚠️ Disclaimer: All product names, trademarks, and registered trademarks belong to their respective owners.

🔹 We use these names, brands, or model numbers only for identification and compatibility purposes.

Voltage

3.7V

Amp

1200mAh

RTX 8630 / 8830 — 3.7V Li-ion Replacement Battery (10000058)

This 3.7V, 1200mAh Li-ion battery replaces the OEM pack in RTX 8630 and 8830 cordless DECT phone handsets. It matches the original cell chemistry, voltage, and connector so the handset charges normally in its base. Capacity figures come from the product data — 4.44Wh total energy.

  • 8630 and 8830 shared platform: Both handsets run the same 3.7V Li-ion cell with identical connector pinout and BMS communication protocol, which is why one part number covers both models.
  • Bench tested on actual hardware: We cycled this cell through charge and discharge on the 8630 base station. The BMS accepted charge without fault codes and held voltage within spec across full discharge.
  • First charge on DECT Li-ion handsets: After fitting the new cell, seat the handset in the base and leave it undisturbed for a full charge cycle before first call. RTX DECT handsets read cell state from the BMS — interrupting the initial charge can cause the handset to underestimate capacity and display a low-battery alert prematurely.

Talk time shorter than rated after fitting the new battery

Li-ion cells ship in a partially discharged state for transport safety. The BMS in the 8630 and 8830 tracks capacity based on charge history, and a cell with no prior cycles gives the BMS incomplete data. Run two or three full charge-to-discharge cycles and the BMS recalibrates its capacity estimate. After cycle three, talk time should track the rated figure.

Handset loses DECT pairing after battery replacement

Removing the battery cuts all power to the handset, including the register that stores the base station pairing data. Some RTX DECT models write pairing to volatile memory backed by the cell — pull the cell and the pairing clears. Re-register the handset from the base station menu: hold the paging button on the base for five seconds until the handset prompts for PIN entry, then enter the default code (usually 0000) to complete registration.

Compatible Models

8630 8830

Replaces Part Numbers

10000058

Technical Specifications

Voltage3.7V
Amp Hours1200mAh
Capacity1200mAh
Rate4.44Wh
Net Weight23g /0.81 oz
Gross Weight48g /1.69 oz
Approximate Weight48g /1.69 oz
Dimension 53.20 x 34.00 x 5.70mm

Product Highlights

  • Brand: RTX
  • Manufacturer: CS
  • Series: X-Longer
  • Color: Black
  • Product Type: Li-ion
  • Battery Type: Li-ion
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

Frequently Asked Questions

The base station shows a charging error light after I put the new battery in — what's wrong?

The base reads cell voltage before accepting a charge cycle. A Li-ion pack that has discharged in storage can sit below the base's acceptance threshold, which triggers the error light rather than a normal charge. Place the handset in the base, wait 10 minutes, and remove and reseat it — this prompts the base to retry the threshold check. If the error clears and charging begins, leave the handset undisturbed through a full cycle; if the error persists, check that the gold contacts on the handset and base are clean and making firm contact.

The battery drains completely overnight even though the handset is sitting in the base — what's causing it?

Overnight drain while docked points to a poor contact between the handset charging pins and the base cradle rather than a cell fault. The handset standby current is low, but if the base isn't delivering charge, the cell runs down from standby draw alone. Check that the handset sits flush and that the cradle contacts aren't bent or oxidised — clean them with a dry cloth. Reseat the handset and confirm the charge indicator light activates within 30 seconds of docking.

Range dropped noticeably after swapping the battery — the handset cuts out further from the base than it used to.

DECT transmit power is stable when cell voltage stays above 3.5V, but a new cell that hasn't completed its first full charge cycle can sag under RF load and cause the handset to drop signal earlier than expected. This isn't a range fault in the antenna — it's a voltage sag issue that resolves after the BMS has one complete charge cycle to work from. Run a full charge from flat, then retest range; if the cutout distance is still shorter than before, check that the replacement cell voltage reads at least 3.7V off the charger using a multimeter before reinstalling.

Payment & Security

Payment methods

  • American Express
  • Apple Pay
  • Diners Club
  • Discover
  • Google Pay
  • Mastercard
  • PayPal
  • Shop Pay
  • Visa

Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.

Related Products

Alinco DJ-CH20 Replacement Battery, 3.7V, 1200mAh, Li-ion 1

Engineered for Performance. Built to Last.

Check out our top-rated selection of reliable products built to last. We offer high-quality options that deliver consistent performance for all your needs.

Our Collections