I have a zippy 4200mah battery. bought it a few years ago. probably over 10 years , i’m not sure. Its hardly been used tbh probably less than 10 charges total.
I went to check on it and charge it for a potential activation tomorrow. The 4 cells read around 3.3v and one cell was 3.1v.
I have balance charged it on the imax b6 charger. it safety timed out at 70 minutes.
after an hour rest i read the cells again and it says 13.5v, 3.49v, 3.48v, 3.26v, 3.35v
Does this mean its time to buy a new smaller battery as i dont think i had the ft817 when i bought this, i used it on a ft480 for a few activations i think before i managed to purchase a ft817.
safe to use? guess its not as cell 3 has only moved from 3.1v to 3.26v after 70 minutes of the charger trying to balance the cells.
Assuming it’s a LiFePo4 after 10 years it’s probably terminal but I would keep using it until it dies.
If it’s a 4S battery you will probably struggle to find a replacement. I haven’t found a supplier in the UK recently but you can get 2S and run them in series.
no i’m not writing it off yet. will run some discharge cycles and slow balance charges through it see it can be massaged back to health but won’t be bothered too much if it doesnt recover.
Charge it again after a small amount of use. My Zippy 4200 LiFe has done 580 activations over 14 years and still goes every time I use it. I just recharge it the evening before I go out on SOTA and it has never let me down even doing 6 activations over 3 days on the one charge one time.
my 12 year old zippy lipo works ok?! It has limited use and was in storage for the last 6 years but I did a controlled discharge and balance charge and KX3 worked great
Mine are 10 years old and far from terminal. I agree with the comments that the battery needs cycling before a better balance is achieved, but you will never get absolute perfection… I never have after any charge on any battery.
Last year I tested mine on a DL24 battery tester and all achieved almost 4AH. Not bad for 10 years use. By contrast, my 2009 vintage 4AH LiPOs are down to around 1.8AH and no longer represent good value in terms of capacity vs weight
The 817 runs well off a LiPO, but I now prefer LiFePO4 technology. Finding a 2AH LiFePO4 battery is nigh impossible nowadays, so I have built a pack of 4 x 18650 LiFePO4s (note: not lithium ion vape batteries) and that easily runs the 817 for a good couple of hours. I have built the pack with a balance lead rather than using a BMS and the iMax B6 charges it fine.
I see here, you say you balance-charged the battery and then later say that it is a LifePO not a LIPO battery. LiFePO4 batteries normally have a BMS built in, so why would you need the Imax charger? You can use it, but set on Lead acid battery type, as there would be no separate charging lead (with the 4 or 5 pin plug) from the LifePO battery.
Are we actually talking about a LIPO rather than LifePO or does your LifePO have no internal BMS and an external cell charging lead?
Not all of them do. There are LifePO batteries that are configured exactly like Lipo batteries with a balance connector. Unfortunately these are now quite difficult to get hold of.
OK, thanks for the clarification, Richard. In that case, I agree with a few replies here that say Anthony should perhaps run the battery through a few discharge/recharge cycles, leaving it long enough to fully charge and if, after that, he still sees the same unbalanced voltages, perhaps it’s time to buy a new battery.
73 Ed.
The Zippy 4200MAH LiFePO4 battery has a balance lead just like LiPOs. The iMax charger suits them fine. I charge mine at 1.5A.
Personally I wouldn’t worry about there being an imbalance. It is not necessarily an indicator of reduced capacity or impending failure of the battery. Swelling would indicate it is on its way out.
I think it is worth cycling the battery to see how it performs, maybe in the shack before taking it up a hill if it the only battery available.
So i did a discharge not a long way but the worst cellw as down to 3.1V. then ran a really slow 0.2 balance charge and it seems to be working fine and was balancing up fine. except the battery i think is already bloated. I dont think the charging has done it, it might have been like this for a while one side feels fine but the other feels like a cushion, a very small cushion. the top of this image i tried to show the slight cushion/ballooning. So i dont think i’ll use it. I dont like ballooning lithium batteries.
This swelling / cushion you describe looks little different to mine. All the wiring is at that slightly rounded end of the battery and it is definitely easier to compress. By comparison, the other end is hard and angular.
Mine haven’t changed since I purchased them. For comparison, I photographed mine.
I’m probably going to break a rule by plugging the battery guys who live in Bethesda, the next village to me. If you want something custom made in terms of LiFePo / 4S / big AmpHrs with a choice of connectors, then they’re worth contacting. Their stock battery range has met my needs with powering both an ft817 & ft857. It’s easier to trawl the list under “batteries > radio control” than use the website search. componentshop.co.uk
