Plantronics CS50 Battery Won’t Hold a Charge? Replace It in 5 Minutes — No Screwdriver Needed

Plantronics CS50 or CS55 dying mid-call or refusing to charge? Don’t replace your wireless office headset—swapping the internal Li-Po battery takes under 5 minutes with zero tools required.

If your Plantronics CS50 / CS55 / CS50-USB wireless office headset:

  • Dies abruptly halfway through an important customer or team call
  • Displays a green charge LED but cuts out immediately under talk load
  • Fails to deliver anywhere near its original 8-hour talk time rating
  • Shows "charging" on the base stand, yet never holds usable capacity

…the headset itself is not broken. The internal lithium-polymer battery has simply aged out after 2–3 years of daily docking and talk cycles.

The CS50 is one of the most user-serviceable wireless headsets ever made — requiring no tools, no soldering, and only 5 minutes of your time.

STARNOVO keeps this dedicated replacement pack in continuous production:

Compatible Replacement: 3.7V Li-Polymer Replacement Battery for Plantronics CS50, CS55, CS50-USB & Avaya AWH-55 Series (OEM: 64399-01 / 64327-01)

1. What Battery Does the Plantronics CS50 Use?

Technical specifications for the OEM-spec replacement cell:

  • Voltage: 3.7V
  • Chemistry: Lithium Polymer (Li-Po)
  • Capacity range: 190mAh – 240mAh high-performance rating
  • Connector type: Factory-molded white quick-disconnect socket (no soldering required)
  • OEM part references: 64327-01, 64399-01, 65358-01, PLN-6439901, ED-PLN-6439901
  • Protection: Integrated PCM protection circuit module against overcharge and short circuits

2. Supported Plantronics & Avaya Models

This replacement pack cross-references a broad range of enterprise wireless headsets:

  • CS50 series: CS50, CS50-USB, CS55, CS55H
  • CS60 series: CS60, CS65
  • CS300 & CS500 series: CS351, CS351N, CS361, CS361N, CS510, CS520
  • Savi wireless: Savi W410, W420, W710, W720, and HL10 lifters
  • Avaya wireless: Avaya AWH-55, AWH-65

Verification Tip: Check your existing battery label to ensure it references part number 64399-01, 64327-01, or 65358-01 before ordering.

3. Plantronics CS50 Battery Swap — Step-by-Step Guide

Tool requirements: None. No screwdrivers or pry tools needed:

  1. Remove the wearing accessory: Detach the ear loop or headband from the headset module.
  2. Locate the battery compartment: Find the battery door on the cheek-side of the headset body, identifiable by its two textured grip tabs.
  3. Squeeze and release: Firmly press both sides of the door cover inward to release the locking tabs.
  4. Slide the door: Slide the cover toward the speaker end until it lifts free.
  5. Disconnect the old cell: Grasp the white plastic connector housing firmly and pull the halves apart. Never pull directly on the wire leads.
  6. Install the STARNOVO cell: Align the white T-tab connector into the headset's socket and press until seated securely.
  7. Tuck the battery: Guide the battery flat into the compartment so the cover will close completely flush.
  8. Snap the door closed: Reattach the outer cover, snap the tabs into place, and reconnect your ear loop or headband.
  9. Initial charge: Dock the headset on the charging cradle for 2–3 hours before returning to calls.

Troubleshooting Tip: If the headset does not power up after installing the new pack, disconnect the battery for 30 seconds, reconnect, and re-dock to the base to reset the internal fuel-gauge circuit.

4. When a New Battery Won't Solve the Issue

Skip the battery swap if your headset setup exhibits any of the following hardware faults:

  • No base power: The base station power indicator does not light up when connected to AC power.
  • Pairing failure: Headset fails to pair or establish a DECT link even after completing a full base re-sync.
  • Physical connector damage: The internal white socket on the headset circuit board is corroded or broken.

These issues stem from base station power supply faults or damaged board circuitry rather than battery wear.

5. Why Enterprise Call Centers Choose STARNOVO CS50 Packs

  • Exact OEM architecture: 3.7V Li-Po form factor with factory-molded white connector clips for solder-free installation.
  • Integrated PCM circuitry: Built-in protection module safeguards against overcharge, over-discharge, and short circuits.
  • Certified compliance: Fully tested and certified under UN38.3, IEC62133, UL 2054, and RoHS safety benchmarks.
  • Full-shift talk time restored: Delivers true all-day talk time for high-volume call center, Teams, and VoIP environments.
  • 12-Month warranty: Direct manufacturer backing with 30-day DOA coverage.
  • Fit verification by photo: Email a photo of your existing battery label to our team for confirmation within 24 hours.
  • Wholesale & bulk supply: Dedicated stock and volume pricing available for IT departments and telecom resellers via sales@starnovo.com.
Get the Plantronics CS50 Replacement Battery →
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