LiPo batteries explained
Batteries are the part most likely to disappoint you and the part most likely to hurt you. Both problems come down to understanding four numbers and a handful of habits.
S: cell count
"6S" means six cells wired in series. Each LiPo cell sits at roughly 3.7V nominal, 4.2V fully charged. So a 6S pack is about 22.2V nominal and 25.2V off the charger.
More cells means more voltage, which means more speed from the same motor — and more strain on everything downstream. Your motors and ESC both state a supported cell range. Both have to allow it.
mAh: capacity
Capacity is how much energy the pack holds. A 1300mAh pack holds roughly half again what an 850mAh pack does.
Bigger isn't automatically better. Capacity comes with weight, and weight costs you flight time and agility. There's a point where adding capacity makes the aircraft slower to accelerate and no longer flies meaningfully longer. Long range builds push capacity high on purpose; freestyle builds usually don't.
C rating: how fast it can deliver
The C rating describes continuous discharge capability as a multiple of capacity. Treat manufacturer C ratings with real skepticism — they're marketing numbers as often as engineering ones, and they're inconsistent between brands.
What matters practically: an underrated pack sags under hard throttle. You'll feel it as a power drop mid-punch, and you'll see it as voltage dipping further than it should.
Connectors: check before you order
- XT60 — standard on 5-inch and larger builds
- XT30 — smaller builds drawing less current
- PH2.0 / BT2.0 — whoops and micros
Connectors are solderable if you own an iron and know how. If you don't, filter by connector and save yourself the project.
Voltage habits that decide pack lifespan
This is the part that separates packs lasting years from packs puffing in months.
- Full charge: 4.2V per cell. Don't go above it.
- Land around 3.5V per cell under no load. Flying a pack down to empty repeatedly kills it.
- Never below 3.0V per cell. Below this, damage is usually permanent.
- Storage voltage is about 3.8V per cell. This is the big one — leaving packs fully charged for weeks degrades them noticeably. Most decent chargers have a storage mode that'll take a pack to storage charge automatically.
Safety, plainly. LiPos can catch fire, and a LiPo fire is fast, extremely hot, and hard to put out. Charge in a fireproof bag or metal container. Never charge unattended. Never charge a pack that's puffed, punctured, or was in a hard crash — set it aside somewhere non-flammable and check it later. After a crash, give packs time before charging: damage isn't always visible immediately.
Buying used
Don't, unless you know the seller. A pack's history — how deeply it was discharged, how it was stored, what crashes it survived — is invisible from the outside and determines everything about whether it's safe.
Before you order: confirm cell count is supported by both your motors and ESC, the connector matches what's on your aircraft, the physical size fits your frame and strap, and you own a charger that handles that cell count.
This is general guidance, not a substitute for your battery manufacturer's instructions. Follow those first — see our disclosure.