Problems with 1S GNB HV batteries?

Anybody has problems with famous and popular 1S HV GNB’s? I have 10 250mAh 1S HV’s and 3 450mAh’s 1S HV’s and quality really varries… I am currently using 5 of 250 and 3 of them lost punch after only 7-8 cycles. With 450 I have even worse result - I just started to use only one for now (got them before 3 days), and it start to sag after only 3 (yes 3!) flights - so I start to use second one and it works perfect on first flight. If it goes off after 3rd useage, it will be really frustrating :frowning:
I charged them mostly on 1c and 1.5c, never overcharged, never discharged below 3.7 (450 I even did not discharged below 3.8 - and it lasted only 3 flights!?), I did not stress them in flight (I care about what “C” I pair with what motors etc.) , I leave them on stock voltage (3.85)…

Could be bad batch or bad luck? Please share your experience…

jap…i know the little problems with small gnb lipos …
i have the best results with ““mylipo”” and ““tbs”” :sunglasses:

gnb above 450mah are great ( imho ) got no problems with them

cheers

I was worried that answer will be like that… :frowning:
I have one mylipo hv 255mah which is still fine after more than 10 flights. I am keeping it for special tricky flights… Need to get more of them but they are very expensive (shipping to my country is problem - either not possible or it is more expensive than battery itself :frowning: - but looks like mylipo.de again ships to my country… need to try to order)

is the main connector at the top of your batteries is loose , some of them are getting really loose especially the 350mah HV 2s which why those was not good after couple cycle …also it depend how you charge them . I guess you are charging them at 0.2a right ?

I heard that 250 tend to get loose - but mine are pretty fixed. It is interresting that one mylipo I have, is a bit loose - and works fantastic (!). 450 has connectors on wires and it is really fixed well on both sides (at battery and at connector sides) - nothing moves after 3 flights - and it can’t deliver enough power any more… :frowning:
I am charging at 1c - max 1.5c ( approx.). That means - 250 I charge at 0.2a or 0.3a while 450 I charged only 3 times at 0.5a. Not exactly 1c and not 1.5c, but somewhere inbetween.

It may well be the connector - JST PH 2.0? - rather than the battery cell itself. Whether it is tight or not means little - that is down to the plastic shell, it is about contact resistance. It gives the impression the cell is failing, but probably it is not.

I have had all sorts of grief with these connectors (which are not rated for enough current) until I started putting a dab of switchclean (WD40 actually) on each time they were charged - otherwise they tend to get hot and tarnish.

I find them OK on up to 75mm with 0720 brushed motors, but someone else with 85mm / 8520 could never get them reliable and had to chage to XT30s, so 75mm 0720 seems to be about the limit.

You mean that connector is worn out? But with 450 I have problem after only 3 flights - which is 6 connections/disconnections (charger + quad)… ph2.0 should not be so problematic like ph1 (or whatever it is called - those small ones on original tiny whoop :slight_smile: ) and it should be durable… and I am using these lipos with ph2.0 on 716 and 720 builds so I am within recommended parameters.
About WD40 - you spray it in connector holes?

Not mechanically worn out, but it may have got too hot. It has nothing to do with how old it is. When they get too hot (due to poor contact area) the resistance goes up, so it gets hotter, resistance goes up, etc and it all thermally runs away.

All those tiny whoop connectors are used well past their specified max. current. The JST PH (which is the bigger one - 2.0mm) is rated at 2A, the Molex Picoblade one (which is the smaller - 1.25mm) is even worse - rated at about 1A.

With an absolutely brand new connector (battery end) you are usually OK, but then minute corrosion builds up, resistance starts to rise, and you are into the above. It can happen after 1 flight or 41 flights. Pure luck.

To give you an example, my 65mm brushed takes about 3.5A to hover, and the 75mm brushed about 5.8A - and that is just hovering. Ie well above the specified connector capabilities. All those connectors have just one strength really - small and light.

I had endless trouble with poor battery life etc, and after investigation it all came down connectors. Any decently rated connector (you need a good 10A) is too heavy, but what I did find is that if I dab each connector with switchclean (WD40 worked best as it leaves a film) each time they are charged, it keeps corrosion away, and - touch wood - I have had not connector / battery problems since.

But, as per original response, I suspect that the limit is my 75mm / 0720, as a friend’s 85mm / 8520 always made the connectors get too hot. Very marginal therefore.

This may be nothing to do with the problem you have, but it is what I found. I keep some WD40 in one of those 2ml bottles with brushes commonly used for nail polish.

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Wery interresting. I’ll try WD40 on second and third 450 battery and inform about results… I assume once they corrode it cant be fixed except with replacing connector - so I’ll try the one that still works fine (2 flights and still OK) and a brand new unused one.
Thanks for tips.

I found that with switchclean, bad batteries were OK again. Not clear why, but possibly the insertion clears some tarnish/corrosion, and the coating stops it coming back…

Interresting. I just sprayed connectors on one 450 (the one with only 2 flights and still ok) and charging it at 0.4A so we’ll see how it goes after I fly with it.
Now, I have some questions about this:

  • do you do this before each charging or no need because WD40 make a thin film and process can be done every 3rd, 4th charge etc. ?
  • do you do this, also, after charging and before connecting to quad?
  • can corrosion be prevented maybe with lover C during charging? I charge with 1c or just a bit more but never at 2c or more…
  • I have WD40 with “a straw” on cap so I “targeted” spraying best I could at small holes on battery connector (with some handkerchiefs I prevented spray to go to the other parts of battery). Is there any better method? I assume you have more efficient way… give some tips please :slight_smile:

On your points:

  1. I put WD40 on every time I charge them. Probably don’t have to, but I just make a regular point of doing it - routine. I don’t do it again until the next charge. One reason for doing it before charging rather than just before flying is that if there is a high resistance terminal, the charger may cut off too early and you don’t get a full charge - I have seen this happen.
  2. I doubt corrosion has anything to do with charge rate, more probably moisture in the atmosphere?
  3. I actually tend to charge all my batteries (big and small) at just under 2C, this on the basis of an article by Gens Ace / Tattu that said most LiPos can be charged at up to 2C with no ill effects. I know it is against received wisdom, but I don’t seem to be getting short battery life, anyway, and it saves time.
  4. Yes the damn stuff got everywhere to start with when I was using the can. What I do now is I have some 2 or 5ml glass bottles with brushes in the caps that I got from Ebay or Amazon. I just have some WD40 in one of those, and dab the battery connector just before charging. It is a really small quantity that is needed - a fraction of a drop.

Good luck with it and I hope it helps. There are lots of other reasons for battery problems - over discharging or charging for example - but this really helped me.

One final point: those connectors have very limited mating cycles anyway, often it is not even quoted in the spec, they are really designed fot internal electronic assembly use, ie build and leave, with maybe occasional disassembly, not continual unplugging. So, lifetime is an issue, but having said that, I now find the cell gives up (eg swelling) before I have connector problems.

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I also got bad result with LIHV, i have test MYlipo.de BetaFPV GNB Infinity they all dont last very long the betaFPV have been the worth.
The thing is that i dont really trust all this battery manufacturers and to me all the small LIVH are just regular lipo i really doubt that they are any different internally. So to me what happen is we are just over charging a regular lipo which result to a shorten life. I’m just gonna stop buying LIHV and stick with regular lipo.
About W40 tips i never heard about corrision on lipo but i know that standard AAA batterry can corrode quicly due to hydrogen gas being released from the acid of the battery, i will give it a try doesnt hurt anything.

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@nmw01223
Regarding corrosion - on some old Eachine batteries with Losi plugs (and on some Boldclash that came with B03 quads), when I stripped wires to shorten them after discharging and before ditching to trash, I noticed on wires some type of oxidation (green rust or something simmilar). So I assume that maybe high current causes this also in connectors on these gumstick LiHVs etiher during charging or useage… Anyway, thanks for info and tips. I’ll definitelly try your method.
Ah yes - I forgot to post that, after I used WD40 on that second one 450mAh’s, I had 3 more flights and it still goes OK. So, in total 5 flights and still strong - far better than non-WD40-treated first 450 which loses power on third flight…Now, can’t be sure if this helped or not (maybe first one was “a lemon”)- but we’ll see with my others batts…

@Chapax
I am aware that they don’t last long - but 7, 8 flighst and especially 3 flights are unacceptable short battery life for any price… :frowning:
I am not sure that they are normal Lipos that you just overcharge. If you try to overcharge nornal Lipo to 4.35 it could puff and produce fire or explode - I seriously doubt any manufacturer will get into that risk by selling normal ones as Lihvs and potentially cause house fires of their customers.
Lihvs are perfectly fine after charging to 4.35 - no puffs, fire etc. I think they are real deal but due to different chemistry, they do have shorter life. But I expect at least 20 charges before starting to lose power - not 3, 7, 8… :frowning:

Alkaline AA/AAA corrosion is normally due to chemical leakage from the cell. What I was meaning was a minute corrosion film building up on connectors just due to moisture and contaminants in the atmosphere. I think that just increases resistance enough to push it over the edge, given they are overstressed anyway.

Pretty much all connectors do this unless gold plated.

I would doubt high current alone would cause it. Green sounds like verdigris, normally caused by exposure to the environment as above. But high current can cause overheating which leads to tarnishing which is the multi-coloured effect you see sometimes (oxidation).

Anyway, the proof of the pudding is in the eating, as they say, so hope it all helps!

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I would doubt high current alone would cause it. Green sounds like verdigris, normally caused by exposure to the environment as above. But high current can cause overheating which leads to tarnishing which is the multi-coloured effect you see sometimes (oxidation).

Anyway, the proof of the pudding is in the eating, as they say, so hope it all helps!

In my case, green stuff on wires were under insulation - from Losi connector and all the way up to the battery. Pretty strange… But yes - need to try your method and we’ll see will it helps in all my cases. Thanks for all tips!

I’ve had 30+ cycles from my GNB 450mah HV and they are still good. I only charge to 4.2v but you have to watch the vsag. Mine dips to 3.3v on full throttle, it probably goes lower but thats as low as silvervise warns you at

With that problematic 450 one and also on second one that is still good, I tested real voltage via telemetry at my Devo and also with AKK A1 OSD camera I put on test quad (it shows real voltage too - it has built in OSD chip) and on both telemetries, both batteries on really full throttle (I tried full throttle and checking voltage by holding quad in hand) never goes below 3.5-3.4. Also, my alarms at Devo are set to 3.7 on compensated battery value. I don’t usually check real voltage unless it start to feel bad… (like in this case).

Here are complete details about all tests I made. Keep reading… :slight_smile:

Problem with all these GNB HV’s I have are - after really small number of cycles (in my case less than 10 - and, as I wrote in previous posts, with one of these 450’s, after only 3!?!) they really loses power. I tested all this with one bad (3 cycles) and with one new, fresh battery (0 cycles) - both charged with 0.4A on Boldclash 6-port charger to 4.35 (actually, it charges a little less - both were at 4.34 after charging which is good - it does not overcharge). First I put bad one, tested, and then I put new one - all in the same Silverised Betafpv lite 75mm 7x20 brushed quad (flashed with some older NFE version).

Tested for only first 30 seconds of each battery (while each batt. is still mostly fully charged and need to have most of punch). Tried bad one (5th charge) first and then brand new one (first charge). Results are:

  • 450 HV that went bad after 3rd cycle (now it is its 5th charge): at throttle punch in hovering, it feels OK but you can hear motors screams - like they are struggle to deliver. Can fly in circles, eights etc. can do flips and rolls… But any tricky and abrupt moves as rapid 180 turns and getting out of dives etc. is problematic and you feel it can’t deliver and then washouts (obviously not enough power to get out of tricky move etc.). Need to slow down in some fast turns or it goes down. After 30 seconds, landed, removed battery. Motors are rather cold but I still wait for about 20-30 seconds and then put brand new 450 HV with 0 cycles, charged first time.
  • 450 HV brand new, 0 cycles, first charge: at throttle punch it feels amazing - instant skyhigh! Motors screams diferently - much less noise - different buzzing… like they don’t need to work much (can’t explain better). Flys amazing - tricky and abrupt moves (180, getting out of dives…) is piece of cake and you feel you can control it easily. No washouts and no lack of power even in moves that require lot of battery power - I tried half rols and then dives and getting out of dives with 180 turns etc. - totally locked in and not a single problem: no washout, no propwash, no vibration, very powerful… and I can catch it even when I almost touch grass - there is enough power to save it in the last moment.

Both does not sags below 3.4 as far as I see in from-hand-test which I did after this (can’t check display while flying :slight_smile: - so sag is tested after 30 seconds of flying of each battery by holding quad in hand and giving full throttle 3 times for 2-3 second in each take)

Note: first problematic battery in first 3 flights was exactly like that second one - full of power and punch. But after 3rd usage, it goes “off” as it is stated above in test. Brand new battery from test, which I charged for the first time, I still need to try more and we’ll see will it hold or also go off after 3-4-5 flights. Third 450 I have I “oiled” with WD40 (as stated in previous posts) and which I used in 5 flights so far, looks OK - I did not notice any dramatic lack of performance - but I’ll try it more today if I find time…

The same behaviour I have with GNBs 250 HVs but after 6-7 cycles (not after 3). With mylipo, I did not notice this on the only one mylipo 255 HV I have - I used it at least 10 times so far and still goes strong… I have similar loses of punch also with them, but only when voltage is near end (when telemetry shows below about 3.85, it starts to loses punch - but that is acceptable) - but in first 30 seconds, it works great!
Of course, I did not used these 250 and 255 on that 75 build because it will drain them and kill them too soon. All tests with 250 and mylipo 255 are done on 7x16 Silverised Boldclash B03 and Beecore lite 65mm builds… (also flashed with some older NFE version)

Strange…

Now, I see you charge them to 4.20 - I noticed that most people do that with HV’s… Maybe it really deteriorates battery quickly if I go with full charge - but I think they still should work more than 3, 6, 7 or even more than 8 cycles… And I so much like that first 30-50 seconds of extra punch that they delivers when they are fully charged at 4.35… That’s great feeling! When it works… :frowning: