The Packs You Wouldn't Fly: A Winter Battery Clear-Out for the Whole Club

There's a box in your shed. You know the one. It's behind the flight box, under the offcuts, and it contains at least three packs you wouldn't dream of putting in an airframe — plus a couple you can't identify at all. Multiply that by the membership and your club is sitting on a small, poorly ventilated warehouse of questionable chemistry.

The good news is that clearing it out doesn't need a committee, a budget or a risk assessment longer than the average club constitution. It needs an evening, a trestle table, a few clear rules and somebody willing to be the one holding the clipboard. Ideally, that somebody isn't the same person who's been meaning to do it since 2019.

Start with the awkward question

Before you book the hall, decide what the club is actually offering. This isn't a recycling service and it certainly isn't a free tip run for every member's entire garage. It's a one-night amnesty for packs that are finished, suspect or unidentifiable — and it works best when nobody has to explain themselves.

No lectures about how the pack got that way. No tally of who has the worst collection. The whole point is to make it easier to hand something over than to quietly keep it, and the moment it becomes a confession booth, half the membership will stay at home with their puffed 3S still in a carrier bag.

Set two or three simple acceptance rules and publish them in the club newsletter a fortnight ahead: model aircraft packs only, no swollen pack carried loose, and everything labelled with the owner's name and the pack's known history — or 'unknown' if that's the honest answer.

The sorting bench

On the night, lay out three zones and keep them physically apart.

Zone one — the quarantine table. This is where everything lands first. Nothing goes straight into a storage box. Packs arrive, get a sticky label, and sit there while somebody with a voltmeter and a pair of gloves gives them a once-over. A metal tray or a lidded steel box lined with sand is the sensible home for anything that looks unhappy.

Zone two — keepers. Packs that pass inspection go home with their owner, ideally with a fresh label showing capacity, cell count and the date. This alone justifies the evening; most members will discover at least one perfectly good pack they'd written off.

Zone three — the outbound box. Dead, damaged and unidentified packs, taped up and bagged, waiting for disposal. This box leaves the building at the end of the night. It does not go back in anybody's shed 'for now'.

Have a fire blanket, a bucket of dry sand and a clear stretch of floor near the door. That's not drama, it's just good manners towards the venue.

Reading a pack without guessing

A cheap digital voltmeter and a bit of common sense will sort most of the pile.

Check each pack's resting voltage per cell. A LiPo sitting well below three volts per cell has been neglected, and one that won't hold a charge at all is a candidate for the outbound box. Look for swelling, soft corners, splits in the shrink wrap, scorched balance leads, corroded tabs or any smell that isn't just 'workshop'.

Swollen means retired. Not 'retired after one more flight', not 'fine if I only use it for bench testing'. Retired.

The same goes for anything with a damaged balance plug, a repaired main lead with dubious solder, or a chemistry you can't identify. If a pack has no label, no balance lead and no owner who can remember buying it, it's a mystery cell, and mystery cells are exactly what this night exists to remove.

Tape every exposed terminal with insulation tape before it goes in the outbound box. A loose pack rolling around in a plastic crate with a bare Deans connector is a genuinely silly way to end an evening.

Getting it gone

This is where UK clubs tend to stall, so plan it before the night rather than after.

Household waste recycling centres are the obvious first call, but accept that practice varies wildly between councils. Most will take ordinary household batteries without a fuss; many are wary of lithium polymer packs, particularly anything swollen. Phone your local HWRC in advance, ask specifically about 'lithium polymer model aircraft batteries', and get a name. Ask whether they want them bagged, taped or handed to a member of staff rather than dropped in a container.

Retailer take-back schemes cover a lot of small portable cells, but don't assume a shop will accept a 6S 5000 pack with a puffed cell. Ask first.

Do not post damaged or suspect lithium packs. Royal Mail and the couriers are clear on defective batteries, and 'it's only a small one' is not a defence anyone wants to test.

If a pack is destined for disposal and you want to reduce its energy first, a controlled discharge through a suitable resistive load, outdoors, on a non-flammable surface, monitored throughout, is one option some clubs use. Others simply label and hand over intact. Either way, keep it outdoors and keep an eye on it, and don't puncture, crush or immerse a pack in salt water on the strength of something you read on a forum in 2011.

Make it a club night, not a chore

Give the evening a shape. Half an hour of sorting, tea, a short talk from whoever did the research on local disposal routes, then the second half for the outbound box and a weigh-in.

Weighing the outbound box is a surprisingly good motivator. 'Fourteen kilos of retired packs out of the membership's sheds' reads better in the club newsletter than any amount of finger-wagging, and it gives next year's event a target to beat.

Keep a simple tally sheet: packs inspected, packs returned to service, packs retired, and where they went. That's the whole record. It gives the committee something to point at if the venue ever asks what the club does about fire risk, and it takes about four minutes to fill in.

The bit people forget

Once the box is gone, it's gone. Don't let it sit in the secretary's garage for a fortnight waiting for a convenient tip run — that's just relocating the problem and adding a car journey.

And do the boring follow-up: a note in the newsletter reminding members to store what's left at a sensible storage voltage, in a cool dry place, in something that isn't a cardboard box under a window. The clear-out is the easy part. Keeping the shed clear until next winter is the habit worth building.