Link is badly formatted (unless you like looking at Rembrandts!): https://www.batterymasters.co.uk/
Found the site anyways, and they don’t appear to sell anything like the Zippy flightmax.
I’ve been checking the Hobbyking site from a UK perspective. The 4200mah Zippy Flightmax LifePo4s are no longer available. The 8000mah is available but there is now a £20 surcharge for delivery, taking the total to around £80. I’m not surprised about this.
I’ve just ordered some Panasonic 18650 LifePo4 cells from eBay to create a KX3 battery, I suspect this is the way we may need to go moving forward if the supply of these batteries dry up.
Their need is probably very much driven by the remote controlled hobbyists.
The two problems I see with the 8000mAh battery is that it’s 105WHr and that could be an issue taking on a plane. The second is the sheer up front cost should your battery swell and fail just after the waranty expires.
I’m super happy with my 4200 and will ensure it’s not abused if it’s now a “collectors item”. I think my LiPos which are 10 years old this year were never 4000mAh but probably 2800/3200 based on performance and also the original cheapo charger never fully charged them. Since moving to a B6 charger, the LiPos do last better.
I think it’s time to invest in one of Luc ON7DQ’s 18650 power packs and cell holder tricks for airplanes etc. anyway.
All,
Back in stock?
https://hobbyking.com/en_us/zippy-flightmax-4200mah-4s1p-30c-lifepo4-pack.html
https://hobbyking.com/en_us/zippy-flightmax-4200mah-4s2p-30c-lifepo4-pack.html
73’s
David
G4ZAO
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Welcome to the SOTA Reflector!
Further to replies above and in a similar vein. An 8.2Ah you would not in theory be allowed on an aircraft which might be why supply is difficult. I ordered a 10Ah about 8 years ago from China and I’m still waiting for it to arrive. Far better to use smaller batteries and harness them together. I have two pairs of 5Ah which I used last weekend. I used to have a 13.2Ah which was actually three 4.4’s in parallel. These big batteries were and sometimes still are used for a 100W radio.
All these have worked well and I have had no trouble apart from the usual swelling which seems to eventually occur with most of them paralleled or not. I un-parallel them for charging normally but I’ve had no problem charging while paralleled on many occasions using just one of the sense/ balancing connectors without trouble. NOT RECOMMENDED however.
You will get more flexibility with smaller batteries and the choice of stacking them or using singly for lighter applications
73, John
………………
Another thread which may be of use to you?
I don’t understand the difference between the 4s1p and the 4s2p, anyone able to help?
4S1P = 4 cells in Series in 1 Parallel bank
4S2P = 4 cells in Series in 2 Parallel banks
For LiFePo, each cell is 3.2V, 4 in series is 13.2 Volts.
The 4s1p 4200mAH has has 4 cells of 4200mAH capacity each in series.
The 4s2p 4200mAH has 4 cells of 2400mAH capacity in series, in parallel with, 4 cells of 2400mAH capacity in series.
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Is there any “better” configuration for our use?
4S1P is made up of 4 cells.
4S2P is made up of 8 cells.
From a probability point of view the fewer cells you have making up your battery, the fewer things you have to go wrong.
But even if you order the 4S1P, you might actually get sent a 4S2P. Hobbyking are a bit like that, and that happened to me, and from the feedback has happened to others. Then you have to ask yourself if you want to go through the pain of sending it back - I just kept mine.
Batteries need a bit of TLC if you want long service from them, i.e. protect them from physical shock, don’t let them get too hot or too cold, always balance charge them, don’t overcharge or over discharge them, regularly check the cell impedance if you have the capability to do so.
In operation both banks will appear and work the same.
73’s
David
G4ZAO
Excellent thank you 
The Zippy Flightmax 4200mha are back in stock shipping from UK warehouse for just over £5 delivery
Ok sorry just read back and found this is old ISH news. Looks like the 1p is out of stock but the 2p is in stock at just over £30
Just for the log: The 4200 mAh and 8400 mAh 4S LiFePO4-packs are back at Hobbyking. Now with yellow heatshrink and labelled “compact” despite the size is exactly the one of the older flightmax series:
https://hobbyking.com/en_us/zippy-compact-4200mah-4s2p-30c-lifepo4-pack.html
https://hobbyking.com/de_de/zippy-compact-8400mah-4s2p-30c-lifepo4-pack-w-xt90.html
73 de Michael, DB7MM
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Thanks for the heads up Michael! 
Reading the description, the burst current rating has gone up from 40C to 60C. That means the 8400mAh battery can deliver up to 504 amps 
! We always say a fuse is probably a good idea; it’s worth repeating. Hopefully the quality will be higher and less variable with this new batch. My old 4200mAh does not hold much charge, although I know other activators have had better luck. I wish there was a 2100mAh version; as a CW only op, I don’t really need 4200mAh.
73 de OE6FEG
Matt
I’ve just ordered 2 x 4200mAh batteries. Hobbyking are doing a Facebook promotion at the moment, I got a message but you may be able to tease the system into life, it gives you a 10% discount.
Note that the postage on 2 x 4200mAh batteries is free, but on the 8400mAH LifePo4 it is just over £20, probably down to the size of the battery and special handling measures.
Regards, Mark. M0NOM
I ordered an 8400 for work, it arrived on a 1m x 1m pallet, on the back of a lorry with Hazmet signs all over it!
The driver then asked where my forklift was to get it off.
The package on the pallet measured 20x20x25cm and weighed 1Kg
We use 2x 4200’s instead now, caused a laugh at the office though.
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Back in stock, just ordered the 4200 one.
OMG that is amazing! Thing is, if they offered free or cheaper delivery on the 8400 mAH that would be happening up-and-down the country!
Thanks for letting us know. I’m presuming you got to keep the pallet…?
Mark.