3.7V 4000mAh LiPo Batteries
3.7V 4000mAh lithium polymer cells for speakers, tablets, medical devices, drones and power banks. Our 4000mAh range runs from a very thin, long 3.3 mm panel (THOR-3377128, 3.3 × 77 × 128 mm) to a compact 12 mm block (THOR-125050), so the same capacity can line the back of a tablet or pack into a rugged deep tool. Compare the finished sizes and request the model that fits your cavity.
4000mAh LiPo Battery Models
All available 3.7V 4000mAh models, sorted by thickness, then width, then length. Use the size tool to match your device cavity, or sort by any dimension.
10 available 4,000mAh models
Finished dimensions depend on PCM, insulation, connector and wire-harness configuration and are confirmed on the engineering drawing for the selected model.
Choosing 4000mAh for Slim Tablets or Rugged Tools
4000mAh is where you decide between spreading the capacity thin and wide or packing it deep. Our slimmest is a remarkable 3.3 mm but large (3.3 × 77 × 128 mm), designed to line the back of a tablet or slim device; the thickest is a 12 mm block (12 × 50 × 50 mm) for power banks and rugged handhelds. Compare each model’s finished thickness, width and length to your usable cavity and leave room for the PCM and harness. If you are weighing 3000mAh, 4000mAh or 5000mAh, the choice is runtime versus footprint — send us your space and target hours and we will confirm.
Need a 4000mAh LiPo Battery for Your Project?
Tell us your available battery space, working and peak current, connector requirement and quantity. Our engineering team will review the selected 5000mAh model and confirm the suitable finished configuration.
- Bare Cell Size
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- Approx. Finished Size
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4000mAh LiPo Battery FAQ
What products use a 4000mAh LiPo battery?
4000mAh suits portable speakers, tablets, medical devices, drones and power banks — larger portable products needing a full day or more of runtime. Our range covers both slim wide panels and compact deep blocks.
How thin can a 4000mAh cell be?
As thin as 3.3 mm, but large in area (THOR-3377128, 3.3 × 77 × 128 mm). A thin 4000mAh cell needs a big flat footprint, so it fits behind a tablet or panel rather than a narrow cavity.
Do you have a compact, deep 4000mAh option?
Yes — about 12 × 50 × 50 mm (THOR-125050), which suits power banks and rugged handhelds where depth is available and you want a small footprint.
How long does a 4000mAh battery last?
Runtime in hours ≈ 4000 ÷ average mA. A device drawing 400 mA runs about 10 hours; one drawing 200 mA about 20. Peak loads, temperature and cut-off voltage affect the real figure.
Should I pick 3000, 4000 or 5000mAh?
It depends on runtime versus space. The sizes overlap, so we recommend choosing by your exact cavity and target hours; send both and we will map them onto the best option.
Can a 4000mAh cell support high current?
Continuous and peak current depend on the cell’s C-rate and the PCM rating. Many 4000mAh models support several amps continuous with higher short peaks. Tell us your continuous and peak current and we confirm a cell and protection board rated for it.