Battery Building ToolsCell Database INR21700-55E

✱ Render

21.78 × 71 mm

21700NMC Mooch-tested · 10 A

Samsung INR21700-55E

Name: Samsung INR21700-55E Lithium Battery Cell
Brand: Samsung

Samsung

Capacity5490 mAh19.76 Wh

Mooch continuous10 ASize to this figure

Resistance16 mΩDC internal resistance

Voltage window3.6 V2.5 – 4.2 V

Standard charge2665 mA~2.1 h to full

Build a pack with this cell →Download spec sheet (PDF)Open the datasheet Mooch's test ↗

At 5490 mAh, this ranks #15 of 72 21700 cells in our database. Mid-range for capacity among 21700 cells. More capacity than 81% of 21700 cells in our database, but lower discharge than average.

Photos from the community

See the wrap, markings, and terminals up close.

Have this cell in hand?

Community photo submissions are opening soon.

Full specifications

Electrical
Chemistry	NMC
Nominal voltage	3.6 V
Max charge voltage	4.2 V
Discharge cutoff	2.5 V
Max continuous discharge	10A (Mooch-tested)
Mooch CDR (trusted)	10 A
Standard charge current	2665 mA
Standard discharge current	1066mA
Internal resistance	16 mΩ
Physical
Form factor	21700
Dimensions	21.78mm × 71mm
Top type	Flat Top
Protected	No
Wrap color	Green
Performance
Capacity	5490 mAh
Energy	19.76 Wh
Energy density	747 Wh/L
Power density (volumetric)	1,361 W/L

Independent test data: Mooch's test of the INR21700-55E ↗

At the standard 2665 mA charge rate, a full charge takes about 2.1 hours. The last bit is a slow taper to top it off.

Voltage operating window

Cutoff
2.5VNominal
3.6VMax charge
4.2V

Usable range: 1.7V

C-rate conversion: Samsung INR21700-55E (5490mAh)

C-Rate	Current (A)	Theoretical runtime
0.2C	1.1 A	5h 00m
0.5C	2.75 A	2h 00m
1C	5.49 A	1h 00m

Highlighted row is closest to the rated 10A continuous discharge.

Charging

Rate	Current	Estimated time
Standard	2,665 mA	~2h 04m
0.5C	2,745 mA	~2h 00m
1C	5,490 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

Download official Samsung INR21700-55E datasheet (PDF) ↗

Pack scaling

Series voltage configurations

Config	Nominal V	Max V	Min V	Common use
1S	3.6V	4.2V	2.5V	Flashlights, single-cell devices
2S	7.2V	8.4V	5V	RC vehicles, 7.2V packs
3S	10.8V	12.6V	7.5V	Power tools (10.8V nominal)
4S	14.4V	16.8V	10V	Ebike (small), some power tools
7S	25.2V	29.4V	17.5V	Ebike (24V system)
10S	36V	42V	25V	Ebike (36V system)
13S	46.8V	54.6V	32.5V	Ebike (48V standard)
14S	50.4V	58.8V	35V	Ebike (52V high-power)
16S	57.6V	67.2V	40V	DIY powerwall

Parallel capacity scaling

Config	Capacity	Energy	Max discharge
1P	5,490 mAh	19.8 Wh	10 A
2P	10,980 mAh	39.5 Wh	20 A
3P	16,470 mAh	59.3 Wh	30 A
4P	21,960 mAh	79.1 Wh	40 A
5P	27,450 mAh	98.8 Wh	50 A
6P	32,940 mAh	118.6 Wh	60 A

Example pack configurations

7S2P

24V ebike / small pack

14 cells25.2V nominal10,980mAh277Wh20A max

13S4P

48V ebike standard

52 cells46.8V nominal21,960mAh1028Wh40A max

16S4P

DIY powerwall

64 cells57.6V nominal21,960mAh1265Wh40A max

4S6P

Power tool replacement

24 cells14.4V nominal32,940mAh474Wh60A max

Design a custom pack with this cell:

Pack Planner →Pack Designer →

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 AudioMight work for smaller setups. Check your amp's peak current draw.

High-Drain VapingBelow the 25A Mooch CDR threshold that high-drain vaping needs. Use a higher-drain cell.

FlashlightsHigh capacity means long runtime. Great for everyday carry and extended use.

Power ToolsMay work for lighter-duty tools. Check your tool's current requirements.

Physical dimensions

Dimensions21.78mm × 71mm

TopFlat Top

Format21700

Similar cells

Same format and chemistry, within ±500mAh capacity:

Cell	mAh	CDR	Wh	Weight	Wh/kg
Samsung INR21700-55E (this cell)	5490	10A	19.76	—	—
Reliance RH60	5850	20A	21.1	71g	297
Reliance RS60	5850	50A	21.1	71.5g	295
Lishen LR2170SK	5800	16A	20.9	—	—
EVE INR21700-58E	5700	16A	20.5	71g	289
Vapcell F56	5600	12A	20.2	74g	272

Build with this cell

Pack PlannerSize your pack. Voltage, capacity, runtime, BMS.Pack Designer2D & 3D layout for your exact cell arrangement Pack BuilderBalance cells by capacity and internal resistance

Frequently asked questions

What is the capacity of the Samsung INR21700-55E?

What is the maximum discharge rate of the Samsung INR21700-55E?

How many INR21700-55E cells do I need for a 48V ebike battery?

Can I use the INR21700-55E for vaping?

What size is the Samsung INR21700-55E?

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.

Get new tools and build tips

We are always adding tools, cell data, and guides. Drop your email for new tool releases and battery-building tips. No spam, unsubscribe anytime.

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.