Snap connector9 V (6LR61)Outer casing · 48.5 × 26.5 × 17.5 mmRed (+) / black (−) wire
- 1Snap connector
- 29 V (6LR61)
- 3Outer casing · 48.5 × 26.5 × 17.5 mm
- 4Red (+) / black (−) wire
Rectangular body, with a small round (+) and a hexagonal (−) snap terminal side by side on top
48.5 × 26.5 × 17.5 mm
48.5 × 26.5 × 17.5 mm
9 V battery
In simple terms
What is this?
A rectangular battery that gathers six small cells in one case; a small bucket under high pressure.
What is it for?
Runs devices that draw little current at high voltage for a long time.
Where do you see it?
Smoke detector, multimeter and guitar pedal.
How do you spot it?
A rectangular box with two snap terminals on its top face.
Caution:
Joining the two ends with metal makes a short circuit and gets hot; connect it with a clip wire.
Technical definition
A rectangular battery containing six small 1.5 V cells in series. Its voltage is high but its capacity is low, so it lasts long only in circuits that draw little current. A clip attaches to the snap terminals on top.
Voltage9 V
Capacitance≈500 mAh
Size48.5 × 26.5 × 17.5 mm
Schematic symbol Same in IEC and ANSI
IEC 60617: the drawing style used in Türkiye and Europe.
Pins 2
1Plus (+)Small round terminal+
2Minus (−)Large hex tip−
Features typical
- Nominal voltage
- 9 V
- Capacitance
- ≈500 mAh (alkaline, at low current)
- Internal structure
- 6 × 1.5 V cells in series
- Nearly done
- ≈5.4 V
- Suitable load
- Low-current circuits
- Example part
- 6LR61 (alkaline)
Common mistakes
Running a motorA 9 V battery can't supply high current; its voltage collapses and it runs out quickly. For a motor use an AA battery pack or Li-ion.
Touching the terminals to metalThe two terminals are side by side; a coin or keys in a pocket can short the terminals and heat the battery.
Test with a multimeter
Test whether this part is good with the multimeter on the measurement screen.
Take a measurementWhere it is used
MultimeterSmoke detectorGuitar effects pedalShort 5 V experiments with 7805
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