Illustrative render of the Vapcell K28 cell✱ Render
Illustrative render generated from published specifications. Not a photograph of the actual cell.
18.3 × 65.4 mm · 48 g
18650NMC Mooch-tested · 20 A

Vapcell K28

Vapcell
Capacity2800 mAh10.08 Wh · 210 Wh/kg
Mooch continuous20 ASize to this figure
Resistance12DC internal resistance
Voltage window3.6 V2.5 – 4.2 V
Standard charge1500 mA~1.9 h to full

At 2800 mAh, this ranks #77 of 279 18650 cells in our database. Mid-range for capacity among 18650 cells. Higher discharge than 77% of 18650 cells in our database. Great for high-drain builds.

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Full specifications

Electrical
ChemistryNMC
Nominal voltage3.6 V
Max charge voltage4.2 V
Discharge cutoff2.5 V
Max continuous discharge20A (Mooch-tested)
Mooch CDR (trusted)20 A
Standard charge current1500 mA
Internal resistance12 mΩ
Physical
Form factor18650
Dimensions18.3mm × 65.4mm
Weight48 g
Top typeFlat Top
ProtectedNo
Wrap colorBlue
Performance
Capacity2800 mAh
Energy10.08 Wh
Specific energy210 Wh/kg
Energy density585.99 Wh/L
Power density (gravimetric)1,500 W/kg
Power density (volumetric)4,186 W/L
Operating Limits
Charge temp0°C to 45°C
Discharge temp-20°C to 60°C

Independent test data: Mooch's test of the K28 ↗

At the standard 1500 mA charge rate, a full charge takes about 1.9 hours. The last bit is a slow taper to top it off.

Voltage operating window

Cutoff
2.5V
Nominal
3.6V
Max charge
4.2V

Usable range: 1.7V

C-rate conversion: Vapcell K28 (2800mAh)

C-RateCurrent (A)Theoretical runtime
0.2C0.56 A5h 00m
0.5C1.4 A2h 00m
1C2.8 A1h 00m
2C5.6 A30m
3C8.4 A20m
5C14 A12m

Highlighted row is closest to the rated 20A continuous discharge.

Charging

RateCurrentEstimated time
0.5C1,400 mA~2h 00m
Standard1,500 mA~1h 52m
1C2,800 mA~1h 00m

These are estimates for the constant-current phase. Real charge time is a bit longer because of the slow taper at the end.

Datasheet

Pack scaling

Series voltage configurations

ConfigNominal VMax VMin VCommon use
1S3.6V4.2V2.5VFlashlights, single-cell devices
2S7.2V8.4V5VRC vehicles, 7.2V packs
3S10.8V12.6V7.5VPower tools (10.8V nominal)
4S14.4V16.8V10VEbike (small), some power tools
7S25.2V29.4V17.5VEbike (24V system)
10S36V42V25VEbike (36V system)
13S46.8V54.6V32.5VEbike (48V standard)
14S50.4V58.8V35VEbike (52V high-power)
16S57.6V67.2V40VDIY powerwall

Parallel capacity scaling

ConfigCapacityEnergyMax discharge
1P2,800 mAh10.1 Wh20 A
2P5,600 mAh20.2 Wh40 A
3P8,400 mAh30.2 Wh60 A
4P11,200 mAh40.3 Wh80 A
5P14,000 mAh50.4 Wh100 A
6P16,800 mAh60.5 Wh120 A

Example pack configurations

7S2P
24V ebike / small pack
14 cells25.2V nominal5,600mAh141Wh40A maxCell weight: 0.67 kg (add ~15% for wiring and BMS)
13S4P
48V ebike standard
52 cells46.8V nominal11,200mAh524Wh80A maxCell weight: 2.5 kg (add ~15% for wiring and BMS)
16S4P
DIY powerwall
64 cells57.6V nominal11,200mAh645Wh80A maxCell weight: 3.07 kg (add ~15% for wiring and BMS)
4S6P
Power tool replacement
24 cells14.4V nominal16,800mAh242Wh120A maxCell weight: 1.15 kg (add ~15% for wiring and BMS)

Design a custom pack with this cell:

Application suitability

PowerwallsHigh capacity means more stored energy per cell. Fewer cells needed for a given kWh target.
Ebike PacksGood balance of capacity for range and discharge for hills. Works well in most ebike packs.
Car AudioEnough discharge to handle amplifier bursts without voltage sag.
High-Drain VapingUsable in regulated mods at moderate wattage. Not recommended for mechanical mods.
FlashlightsDecent runtime. Works well for most flashlights.
Power ToolsSufficient discharge and capacity for most power tool packs.

Physical dimensions

Dimensions18.3mm × 65.4mm
TopFlat Top
Format18650

Similar cells

Same format and chemistry, within ±500mAh capacity:

CellmAhCDRWhWeightWh/kg
Vapcell K28 (this cell)280020A10.0848g210
LG LGABE1186532009A1249g245
LG LGEBE1186532004.9A1249g245
Samsung ICR18650-32A32006.4A1250g240
Sanyo NCR18650GA330010A11.948g248
EVE EVE-INR18650/33V320010A11.5

Frequently asked questions

Handling and safety

Lithium cells can be dangerous if mishandled. A few things to keep in mind:

  • Never charge above 4.2V or discharge below 2.5V.
  • Store cells at around 3.6-3.8V (roughly 40-60% charge) for long-term storage.
  • Don't mix cells with different capacities, chemistries, or states of charge in a pack.
  • Inspect wraps before use. A torn wrap can cause a short circuit.
  • Always use a BMS or balance charger appropriate for your pack configuration.
  • Keep cells away from metal objects, keys, and coins. A short across the terminals can cause fire.

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Specs come from manufacturer datasheets and independent testing; Mooch-tested discharge ratings are shown when available because they reflect real continuous performance better than headline datasheet numbers. Browse the full 18650 & 21700 cell database to compare every cell.

Disclaimer: We do our best to keep the information on this page accurate, but we cannot guarantee that all specifications are correct or up to date. Cell characteristics can vary between production batches and may change over time. Do not rely solely on this data for safety-critical applications. Always verify against the manufacturer's official datasheet before use.