2 x AA Battery Holder with Knife Switch

9V Battery Holder

Holder with 5.5 × 2.1 mm center-positive barrel output. It connects a 9 V battery; it is not a regulator.

9V to Barrel Jack Adapter

Passive 9 V battery to 5.5 × 2.1 mm center-positive barrel adapter for boards that accept 9 V barrel input.

9V Battery Snap

PP3 snap lead for wiring a 9 V battery into a circuit. Check lead polarity and add regulation/protection elsewhere if needed.

Lithium Ion Polymer Battery - 3.7v 1200mAh

Single-cell 3.7 V LiPo pack with JST-PH connector and protection circuit. Needs LiPo-safe charging and polarity checks.

4 x AA Battery Holder with On/Off Switch

CR2032 Lithium Coin Cell Battery

3 V non-rechargeable CR2032 coin cell for low-current designs. Not a motor, radio or 9 V replacement.

PowerBoost 1000 Basic - 5V USB Boost @ 1000mA from 1.8V+

Lithium Ion Battery - 3.7V 10050mAh (10 Ah)

Large single-cell 3.7 V Li-ion pack, listed by Adafruit as 10,050 mAh, about 37 Wh. Same voltage class as 1S LiPo packs, but much larger and subject to fit, shipping and current checks.

Lithium Ion Polymer Battery - 3.7V 350mAh

Small 1S 3.7 V LiPo pouch pack. Same chemistry family as the 500 mAh, 1200 mAh and 2500 mAh packs, but runtime, size and current headroom change.

Lithium Ion Polymer Battery - 3.7v 2500mAh

Medium 1S 3.7 V LiPo pouch pack. Useful when the design already expects a single-cell LiPo and has enough verified enclosure clearance for the larger pack.

Lithium Ion Polymer Battery - 3.7v 500mAh

Small 1S 3.7 V LiPo pouch pack. A capacity change is usually easier than a chemistry or voltage change, but connector polarity and current still need checking.