# DEWALT 20V MAX 5 Ah Lithium Ion Battery DCB205

- Manufacturer: DeWalt
- Tier: S
- Price: $74.50
- Stated capacity: 5 Ah
- Amazon listing: https://www.amazon.com/dp/B00KQU1ENG?tag=lithiumsteppe-20
- Battery page: https://www.lithiumsteppe.com/battery/dewalt_oem_5ah

## Summary

Top-notch construction and extremely high quality cells; DeWalt's own battery is undisputed. You pay for it, though.

## Ratings

- **Honesty**: 4.7/5 — Dead-on for 5 AH @ 18V nominal. Note the pack does state " 100 Wh" on the back, which is false.
- **Durability**: 4.2/5 (teardown 5/5, cycling 3.3/5) — Industry-leading tool contacts are unlikely to bend out of shape. Pack electrical construction is top-notch.
  - Teardown notes: Industry-leading tool contacts are unlikely to bend out of shape. Pack electrical construction is top-notch.
- **Capacity**: 4/5 — High capacity; the Samsung INR18650-25R is an excellent power tool cell.
- **Power**: 4/5 — Excellent performance thanks to solid electrical construction and great 18650 cells.
- **Safety**: 4/5 — Samsung cells are very reliable and robust, combined with great pack electrical design.

Scoring rules: https://www.lithiumsteppe.com/methodology

## Testing statistics

- Stated capacity: 5 Ah (90 Wh @ 18 V)
- Measured capacity: 5.0 Ah (89.2 Wh @ 18 V)
- Pack internal resistance: 57.4 mOhm
- High-power cycles survived: 13
- Peak sustained power: 961 W
- Energy delivered (failure test): 46.0 Wh

## Cell notes

Samsung SDI INR18650-25R. Rated 20 A max continuous discharge, 2500mAh capacity.

## Test data

Test procedures: https://www.lithiumsteppe.com/test-procedures

- **Pack Internal Resistance Test** (rinternal): Pack Resistance: 57.4 mOhm (average value of pack resistance between 17.5 and 18.5 V)
  - CSV: [rinternal.csv](tests/rinternal.csv)
  - Bench source file: rinternal_dewalt_oem_5ah_260506-19-51-10_post-update-t1.csv
- **Capacity Test** (capacity): Capacity: 89.2 Wh (99% of stated 5 Ah @ 18V Nominal)
  - CSV: [capacity.csv](tests/capacity.csv)
  - Bench source file: capacity_dewalt_oem_5ah_260506-15-29-52_t1.csv
- **Cycling Test** (performance): High-power cycles survived: 13. Failure mode: Battery thermistor reached cutoff
  - CSV: [performance.csv](tests/performance.csv)
  - Bench source file: dewalt_oem_5ah/performance_dewalt_oem_5ah_260528-10-32-08_0.csv
- **Failure Test** (failure): Energy discharged: 46.0 Wh, Peak power: 961 W
  - CSV: [failure.csv](tests/failure.csv)
  - Bench source file: dewalt_oem_5ah/failure_dewalt_oem_5ah_260518-14-07-43_2-rerun.csv

### CSV format

1 Hz samples. Lines starting with `#` are run metadata (test profile, battery profile, instrument identity, Arduino DAQ channel labels); the first non-`#` line is the column header. Columns vary by run date — Arduino DAQ columns (tc/v/r_ntc/fault) appear on runs logged since 2026-05-11.

- `ts_unix / ts_iso` — sample timestamp (Unix seconds / ISO-8601 local time)
- `elapsed_s` — seconds since test start
- `voltage_v` — pack voltage, V (4-wire remote sense)
- `current_a` — discharge current, A
- `active_power_w` — discharge power, W
- `discharged_ah / discharged_wh` — integrated charge / energy removed
- `phase / target / cycle` — load-profile phase name, setpoint, loop count
- `tc1_C..tc4_C` — Type-K thermocouple temperatures, Celsius (nan = channel absent, disabled, or faulted)
- `v0_V` — DeWalt C3 cell-tap voltage, V
- `v1_V` — DeWalt TH thermistor-pin voltage, V
- `r_ntc_ohms` — pack NTC thermistor resistance, ohms, derived per-tick from v1_V and pack voltage (DeWalt tool thermal cutoff reference: 2140 ohms)
- `fault1..fault4` — MAX31856 status byte per thermocouple, hex (00 = healthy)

## Photos

- Headline photo: photos/headline.png
- Teardown 1: photos/teardown_1.jpg — Pack external did not visible melt after failure test
- Teardown 2: photos/teardown_2.jpg — Cell venting out of pressure relief holes on bottom of pack
- Teardown 3: photos/teardown_3.jpg — Heat accumulating on cell-side of positive terminal busbar
- Teardown 4: photos/teardown_4.jpg — Robust tool terminals resist bending / deformation. High quality current routing from cells through PCB
- Teardown 5: photos/teardown_5.jpg
- Teardown 6: photos/teardown_6.jpg — Cell label: INR18650-25R +2500mAh CCC- 5 SDIPCMM
- Teardown 7: photos/teardown_7.jpg

## Files in this dataset

- `README.md` — this file
- `site.json` — the published data record for this battery (machine-readable)
- `tests/{rinternal,capacity,performance,failure}.csv` — raw bench CSVs (see CSV format above)
- `photos/` — headline + teardown photos (captions above)
- `test_procedures.md` — the four bench tests
- `ranking_methodology.md` — how ratings are scored

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Source: Lithium Steppe (https://www.lithiumsteppe.com) — We test DeWalt-compatible power tool batteries on Amazon to guide your purchasing decisions.
Generated: 2026-07-16T19:29:36.433Z (site commit a353b4a)
Contact: https://www.lithiumsteppe.com/contact
