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Small black rectangular Li-Polymer battery pack

Centenex Electronics

Centenex Electronics DS-CS-SBA370SL Li-Polymer battery 3.7V 270mAh 1.00Wh black

SKU CH-Y397-AX557

Replacement lithium-polymer battery for Sennheiser headphones, 3.7 V 270 mAh 1.00 Wh, black

  • TypeBluetooth Headset
  • Compatible with Sennheiser MM and PXC headsets
  • Li-Polymer chemistry delivers 3.7V 270mAh capacity
  • 00Wh energy rating powers extended listening sessions
  • Slim 38.40 x 30.70 x 6.60 mm profile fits original battery bay
  • Replaces OEM part numbers 0121147748 and BA-370PX

Replacement battery for Sennheiser headsets

This Li-Polymer cell delivers 3.7 V and 270 mAh capacity in a 38.40 x 30.70 x 6.60 mm black pack. It matches the original BA-370PX part number 0121147748 and fits models including PXC 310 BT, MM 400, MM 450 and MM 550 series. The unit is new and rated at 1.00 Wh.

Direct OEM-compatible swap

No extra cables, adapters or firmware are bundled; the battery simply replaces the worn original and restores the headset's rated runtime. Because it uses the same 3.7 V chemistry, the existing charge circuit manages it without software updates. The 270 mAh capacity mirrors the factory specification.

Simple two-wire installation

Open the earcup, unplug the old pack and connect the new one observing polarity — red to positive, black to negative. The main risk is reversing the leads, which can damage the charging IC. No soldering is required if the original connector is reused; take care not to pinch the thin wires when reassembling.

Highlights

  • Compatible with Sennheiser MM and PXC headsets
  • Li-Polymer chemistry delivers 3.7V 270mAh capacity
  • 00Wh energy rating powers extended listening sessions
  • Slim 38.40 x 30.70 x 6.60 mm profile fits original battery bay
  • Replaces OEM part numbers 0121147748 and BA-370PX

Specifications

BrandCentenex Electronics
ModelDS-CS-SBA370SL
TypeBluetooth Headset

Questions about this item

When will the 1.00 Wh Li-Polymer cell need replacing?

The 270 mAh pack is rated for hundreds of charge cycles; expect replacement when run-time drops below half of the original 1.00 Wh capacity.

What capacity limit appears first during a full day of playback?

The 270 mAh capacity is the limiting factor; continuous use will deplete the 3.7 V cell in a single session.

Does the 38.40 x 30.70 x 6.60 mm pack get warm during all-day use?

Li-Polymer chemistry stays cool at the low 270 mAh draw; no noticeable heat builds up inside the headset cavity.

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