Whilst preparing for our recent expedition I noted with some dismay that my very first 2,200mAh 3S LiPo, given to me by Gerald, G4OIG early in 2009 and veteran of a few hundred activations, had decided to throw in the towel. It had begun to swell, so despite it still being balanced to within 0.02V at it’s storage voltage of 3.8V per cell I decided it was time to consign it to the great recycling yard in the sky
I connected a 100 ohm 3W resistor across it, and left it out on the patio to slowly fade away whilst I took some of it’s younger siblings up a few Scottish summits On my return, it’s terminal voltage had dropped to around 200mV so I deemed it safe to strip and twist together the load wires, before taking it to the local recycling facility.
If you find yourself in a similar situation, please please DON’T take what seems to be the almost universal advice on the forums and dump your dearly departing in a bucket of salt water, or even worse puncture it/slash it open then dump it in the salt water - at best this wont work too well (the aluminium tabs on the cells quickly corrode away, leaving them impossible to discharge) and at worst the physical damage could lead to violent expulsion of the battery’s innards in your direction, or fire…
Similarly, throwing the battery in the domestic refuse once discharged though often recommended is not a good idea - LiPos do contain transition metal compounds - usually cobalt, nickel or manganese - and it’s better for these not to end up in landfill!
Final observation - the original battery stayed hard and flat throughout it’s working life, whereas the newer replacements all seem to get bloated with gas after a few charge cycles - is it just me or is it a widespread phenomenon?
However our local council recycling centre take LiPo plus many other types of batteries but if someone drops a car battery in the box on an old LiPo now that would be a blast.
On two separate occasions, I’ve had LiPo batteries explode. Both were about 3 years old and had experienced the bloating issue. One I just tossed in the trash at the motel (shame on me but, I didn’t want to drive 500 miles home with it emitting a seemingly toxic odor inside the jeep), the other I took back to where I purchased it. What they did with it I don’t know. I’m now using an automobile jump-start Lithium Ion battery that also could serve as a LED flashlight and cellphone/camera charger - 2700 mAh (12v). This battery can be charged from the dashboard accessory jack or a USB port on a PC so, I don’t need to purchase a separate charger for it. Weighs about the same as my KX1. Been using it for a couple years now without any issues. I had a couple other LiPo batts that, though they were not bloated or spent, were disposed of properly at a recycling dump.
last december I also put my 3S 2200 mAh in the recycling facility.
I used mine for about 5 years and did 130 activation.
My batt started swellling a bit one year ago and I recently noticed a little degradation as the voltage dropped quicker during the activation (a new batt could work over 12 V for some time meanwhile the old one quickly reduced voltage to 11,3 Volts).
I didn’t know if I had to discharge it prior to deliver it to the facility so I put it to nominal value (11,1V) and that’s it. Next time I try to find a resistor to fully discharge if it’s better.
My replacement battery is exactly the same model and after 2 months is still hard and flat with good performance.
Three of the four 4000mAH LiPos that I purchased in 2009 are still flat and hard. Two newer 2200mAH batteries have swelled, but the outer packaging can be compressed such that it is evident that the battery inside is still flat and in good health. Indeed one is of quite recent manufacture (2016) and the swelling occurred after only a few charge cycles. This leads me to believe there has been a change in the material encasing the batteries at some point in time, probably to keep costs down.
The one 4000mAH battery that did fail was down to it being accidentally discharged to too low a voltage. It swelled and I discharged it through a resistor before sitting it in salt water for two weeks, after which it went into the waste bin. Unfortunately such was the recommendation generally given at the time.
Thanks to everyone for the feedback. Looks like the newer LiPos are prone to gassing, though doesn’t seem to affect their longevity that I can determine thus far.
Would be interested to know what brand of battery this is, Ignacio
No shame in that, the advice was ubiquitous at one time. In fact I understand the “slash and salt bath” suggestion originated from a LiPo supplier, retracted when people started getting injured but by then it was out there…
I remember what a revolution it was for me to go from lugging 4 and 7 Ah SLABS up hills to a 3S LiPo… I couldn’t contemplate going back now, despite the extra husbandry required! but à chacun son goût…
Good to catch you from GM earlier in the week Geoff, it’s been a long time !
On my return, it’s terminal voltage had dropped to around 200mV so I deemed it safe to strip and twist together the load wires, before taking it to the local recycling facility.