LiPo batteries are the most expensive consumable in FPV, and the one most pilots know the least about. Treat them well and they'll give you hundreds of punchy flights. Treat them badly and they'll puff, sag and eventually become a fire risk.
Our LiPo packs explained post covers what the numbers on the label mean. This one is about keeping them alive.
The Voltages That Matter
| Per cell | What it means |
|---|---|
| 4.20V | Fully charged (standard LiPo) |
| 4.35V | Fully charged (LiHV packs only) |
| 3.80–3.85V | Storage voltage |
| About 3.5V resting | Time to land |
| Below 3.0V | Damaged territory. Avoid |
Multiply by the cell count for the whole pack. A 6S pack at storage, for example, sits around 22.8–23.1V.
Charging
- Always balance charge. Plug in both the main lead and the balance lead so every cell finishes at the same voltage.
- Use the right mode. LiPo mode for standard packs, LiHV only for packs labelled LiHV.
- Charge at 1C unless the pack says otherwise. For a 1300mAh pack, that's 1.3A. It's slower than fast-charging, but your packs will last longer.
- Never leave packs charging unattended, and charge on a non-flammable surface or inside a LiPo bag.
- Let hot packs cool before charging them after a flight.
A good smart charger does most of the work for you. Have a look through our chargers. For whoops, a dedicated 1S charger like the VIFLY WhoopStor 3 can charge and also bring packs down to storage.
Storage: The Most Important Habit
If you take away one thing from this post, make it this: don't leave packs sitting full.
A LiPo left fully charged for days ages much faster and is far more likely to puff. If you're not flying within a day or so, put the packs to storage voltage. Most smart chargers have a Storage mode that charges or discharges each pack to around 3.8V per cell automatically.
Where you store them matters too:
- Somewhere cool and dry, inside a LiPo bag or a fireproof container
- Never in a hot car. In Townsville summer, a car interior gets hot enough to damage packs and is a genuine fire risk
- Away from anything flammable, and not loose in a backpack where the leads can short
Flying Habits That Save Packs
- Land earlier. Pulling packs down near empty every flight is the fastest way to wear them out. Set a voltage alarm and respect it.
- Watch for sag, not just the number. Voltage drops under hard throttle and recovers when you back off. Judge by the resting voltage after landing.
- Don't fly hot packs back to back. Give them time to cool.
Checking a Pack
A cheap battery checker is one of the best things you can own. Something like the ISDT BG-8S shows every cell's voltage in seconds, so you'll spot a weak cell before it ruins a flight.
Healthy cells should sit within a few hundredths of a volt of each other. If one cell keeps drifting away from the rest, the pack is on its way out.
When to Retire a Pack
Stop using a pack if it:
- Is swollen or puffed, even slightly
- Has a dented, punctured or split wrap
- Gets hot while charging or sitting still
- Has a cell that won't hold voltage or won't balance
- Has been crashed hard and looks damaged
Puffing is gas building up inside the cells. Don't squash it back down, don't puncture it, and don't charge it again.
Disposing of a Dead Pack
LiPos don't go in the household bin. Discharge the pack fully (many chargers have a discharge mode), keep it in a LiPo bag, and take it to a battery recycling drop-off. If you're unsure, bring it into the shop and ask us.
Travelling and Shipping
Flying to a race with your packs? Read Travelling with LiPos first. And if you're ordering from overseas, LiPos are dangerous goods, so we can only ship them within Australia. Our dangerous goods guide explains why.
Ready for New Packs?
Browse our full LiPo range, from 1S whoop batteries up to 6S, plus straps, grips and bags in battery accessories. Or drop into the shop at 22 Castlemaine Street, Kirwan, and we'll check your old packs for you.