How to Choose the Right Lithium-Ion Battery Pack

Looking for a battery pack for your RC build, FPV goggles, or DIY electronics? Here’s what to know before you buy.

Lithium-ion battery packs are a great choice for DIY projects because they’re lightweight, rechargeable, and offer high energy density. But with so many options—like 18650 vs. 21700, 2S1P vs. 2S2P—how do you choose?

Understand Your Power Needs

• Voltage: Most RC and portable devices run on 7.4V (2S). If you’re powering fans, LED strips, or Arduino setups, a 2S pack is usually enough.
• Capacity: Measured in mAh. A 2500mAh pack lasts shorter than a 5000mAh one but may be smaller and lighter.
• Current Draw: Look for packs rated for higher amps (20A, 30A, 40A) if you’re powering motors or tools.

Battery Cell Types

• 18650 cells: Popular for compact builds and lower current applications.
• 21700 cells: Bigger, more powerful—great for longer run times or higher loads.

At RenewSpark, we build and test each battery pack in California using new cells from Molicel and Samsung—brands trusted by professionals.

Whether you’re building a robot, modding a tool, or powering a mobile camera setup, we’ve got the right pack for you.