LiPo batteries for AEGs: choosing, charging, storing, and what not to do
For a first LiPo, buy two 7.4 V packs of 1,100–1,300 mAh at 20C or better, a balance charger, and a LiPo safety bag. Go to 11.1 V only once you know the gearbox can take it. Stop at 20% remaining, store at half charge, and never charge unattended.
Reading the label
A pack reads something like “7.4V 1300mAh 25C”.
- 7.4 V (2S) or 11.1 V (3S): voltage, set by the cell count. Higher voltage spins the motor faster: snappier trigger, higher rate of fire.
- 1300 mAh: capacity. A stock AEG draws roughly 1 mAh a shot, so 1,300 mAh is about 1,000 usable shots. Run your gun’s numbers in the battery life calculator.
- 25C: discharge rating. Capacity × C is the maximum current: 1.3 Ah × 25 = 32.5 A. AEGs are happy on 15–20C.
Form factors: stick (buffer tubes and fixed stocks), nunchuck (crane stocks), mini and brick (handguards and AK stocks). Which fits is set by the gun; check the manual or an owner’s review of your model.
7.4 V or 11.1 V
| 7.4 V | 11.1 V | |
|---|---|---|
| Rate of fire | Standard | About 1.5× |
| Trigger response | Standard | Fast |
| Gearbox stress | Low | High; pre-engagement risk on stock gearboxes |
| Who it’s for | A first pack | Guns with upgraded internals |
Japanese-market AEGs (Tokyo Marui and others) are generally rated for 7.4 V LiPo or 8.4 V NiMH only, and warranty cover ends at 11.1 V. Stock Marui gearboxes handle 7.4 V well and 11.1 V badly. The gear ratio calculator shows what each voltage does to rate of fire.
Charging
- Always balance-charge. Plug in the small white balance lead so the charger equalises cells.
- Charge at 1C or less (1.3 A for a 1,300 mAh pack); 0.5C if you’re not in a hurry.
- Stay with it. Nearly every LiPo fire happens on the charger.
- Charge inside a LiPo bag or on a non-flammable surface.
A charger sold as LiPo-capable with a balance port will do this. Avoid USB “trickle” chargers that lack balance leads.
Using
- Swap at about 20% remaining: 3.7 V per cell, about 7.4 V under light load on a 2S pack. Running flat is what kills LiPos.
- “Use it until it stops” is a NiMH habit. Don’t carry it over.
- Don’t leave packs in a hot car. Above about 60 °C they swell.
Storing
For any gap longer than a week, store at 50–60% charge, about 3.8 V per cell. Chargers call this “storage mode”. A pack left fully charged for a month loses noticeable capacity for good.
Keep packs in a LiPo bag, out of sun and heat. No need for a fridge.
If a pack puffs
A swollen pack has gas inside and is finished. Using it risks fire.
- Stop using it and put it in a LiPo bag.
- Discharge fully in salt water (about 50 g salt per litre) for a day or two.
- Dispose of as a rechargeable battery under local rules; in Japan, electronics stores take them in the small-battery collection box.
How many packs for a game day
A typical open day is 8–12 games. At 200 BBs a game that’s around 2,000 rounds, which is two 1,300 mAh packs; most people carry a third. Some fields offer charging power, but charging where you can’t watch the pack is a worse idea than carrying one more.