Topic: 'Instant' batteries

I've been using these AA packs for 2 or 3 years now and rate them highly. Satinet gave me a link to a site that sold 4 cell AAA Instant pacts and the blurb about them says -
 
''For these cells to keep there ability of storing the capacity for long periods of time, it is best that these cells be cycled not just topped up, When these cells are topped up they loose their ability to store capacity for long periods of time.''

It's the first time I've seen this advice and must admit I tend to 'top up' and have seen no tendency for the cells to self discharge any more than when they were new.

Comments anyone?

i don't use any AAA packs at the moment. but I think you need to take that statement in the context of a non rc use. I mean - most nimh batteries are charged by trickle chargers and wall-warts etc. not decent peak detect chargers like most of us use.

in terms of the AA packs I have some that are a couple of years old and I cycled them - the capacity was virtually the same as a couple of years ago and they have probably only been cycled a couple of times in those two years and topped up loads of times.

in terms of the AA packs I have some that are a couple of years old and I cycled them - the capacity was virtually the same as a couple of years ago and they have probably only been cycled a couple of times in those two years and topped up loads of times.

Yes, the same for me too. I sometimes use the wall chager but usually a peak detect chager at .3 Amp for the 2100 mA packs. I have one Tx pck that's lost about 20% capacity in 3 years and I left the Tx on over night on more than one occasion. I still sometimes use it as a back up as there is a voltage display on the Tx to keep me out of trouble!

I usually charge about 0.3C (700 mah). But I am happy to charge more if I am in a rush. Never had a problem with doing it up to 1c on any NiMH to be honest. 

Had nothing but grief with AAA's - they are the 'wrong' shape really - short and fat is better for the 'wiggly electrons' to do their thing!

Had nothing but grief with AAA's - they are the 'wrong' shape really - short and fat is better for the 'wiggly electrons' to do their thing!

Grief for me too. I hate them. Fast self discharge, short life span da da da.
I have an electric pepper grinder, they work fine in that.
My Sanyo's and GPs self discharge 50% in a couple of weeks and can only achieve 50-60% of capacity and are only 8 or 9 months old. Ugh.

I'm trying yet another alternative quite simply because I cannot get any other size into two of my models.....So far my AA Instants are all perfect after 2-3 years. We'll see.Steve.

2 packs ordered on line from ModelPower at 3pm Friday, delived by post 9.30 am Saturday.

i ordered 2 packs wednesday, postie bothered to turn up 2pm friday by which time i couldn't wait any longer and had to go out so missed him by 10 mins.
effing post office  

Ordered a pack of Instants from Vapextech and had them within 24 hours. I don't use anything else.

I was about to place a comment in one of the "Instant" 2100mAh threads today, but ran out of time and went flying.

While there, another member turned up and without any comment from me started bemoaning the "Instant" Tx battery he had just removed from his Tx, it having failed prematurely.

Swapping notes, he's had exactly the same issues as me, namely:-

1. They do not do what they say and hold charge no better than ordinary NIMH.

2. They soon deteriorate to a much lower capacity than stated.

I bought two, he had bought one, all three failed prematurely.  We are both pretty long term experienced with NIMH/NICAD/LiPo batteries, both electrical profession. I was going to post because my second one had failed.

In my case I personally own 7 Tx's, and operate every week often several time s aweek with near 40 more (Yes, 40, all types, but all with AA sized cells!).

I read what people say about the "Instant" type being great, and wonder................why is what is reported by others so different to my (and his) experience? As far as I can tell the only difference in treatment is that I have been putting them through far more use/cycles than club "fly once a fortnight" modellers.

I stopped buying the "Instant" type after the first premature capacity failure, reverting to "normal" 2600mAh NIMH (from Vapextech).

Have not had any issues with any of the 2600mAh NIMH apart from one that was supplied with low voltage and would not recover back to expected voltage, though the capacity seemed still OK. This was swapped without question by Vapextech.

I read what people say about the "Instant! type being great, and wonder................why is what is reported by others so different to my (and his) experience? As far as I can tell the only difference in treatment is that I have been putting them through far more cycles than club "fly once a fortnight" modellers. He is also a very frequent flier.

why do you keep cycling the batteries all the time?

I have most of my models on vapex instants and have never had a problem with them. I am not saying that I would have had a problem on normal batteries either, but there hasn't been an issue.

in fact the only cells i've had fail were sanyo 2600 AA nimhs.  

I would imagine the failure rate or rate of "duds" (i.e never worked) would be similar to normal cells.  In my experience with vapex instants they don't hold a charge like the sanyo eneloops but they are certainly better than normal cells for discharging. well other than that they work so I tend not to think about it too much.

why do you keep cycling the batteries all the time?

Because I'm using them..........................

I'm curious that you've had so much trouble with them.

I've actually sold thousands of Instant packs through my ebay shop sailplaneworld and have had very few instances where packs have been faulty. When there has been a problem in nearly all cases it has been caused by unsuitable charging, normally with a trickle charger with too high a charge rate that was left on after the pack was fully charged.

Can you give some indication of what charging methods you use?

Incidentally, if the Vapextech packs were unreliable I simply wouldn't sell them as I only do it as a small sideline to subsidise my hobby and don't need any hassle.

Because I'm using them..........................

I mean why not just top them up, rather than send them through a full discharge -> charge cycle.

Sorry, confusion creeping in here, I wrote "cycles" as in charge from last state and then use discharge, not "cycling" as in full cycle using discharge on the charger. Meaning to say, they get more use than most "hobby" people would apply.

There is nothing abnormal about the charging regime, I have several Futaba Tx/Rx chargers for trickle and a Graupner Ultramat 16.

Bottom line is that all my Vapextech 2600mAh packs are fine, some of which pre-date the Instant packs, and both my Instants have failed. They effectively got the same treatment.

This second failure was fully cycled twice this morning to see what it would do, it was reaching discharge cut-off after 270-295 mAh, and stopping recharge after 580-630mAh...consistent.

Sorry, confusion creeping in here, I wrote "cycles" as in charge from last state and then use discharge, not "cycling" as in full cycle using discharge on the charger. Meaning to say, they get more use than most "hobby" people would apply.

There is nothing abnormal about the charging regime, I have several Futaba Tx/Rx chargers for trickle and a Graupner Ultramat 16.

Bottom line is that all my Vapextech 2600mAh packs are fine, some of which pre-date the Instant packs, and both my Instants have failed. They effectively got the same treatment.

This second failure was fully cycled twice this morning to see what it would do, it was reaching discharge cut-off after 270-295 mAh, and stopping recharge after 580-630mAh...consistent.

What charge rate were you charging at?

I was about to place a comment in one of the "Instant" 2100mAh threads today, but ran out of time and went flying.

Swapping notes, he's had exactly the same issues as me, namely:-

1. They do not do what they say and hold charge no better than ordinary NIMH.

2. They soon deteriorate to a much lower capacity than stated.

This is very strange. I have used instants (both Vapex & Enloops) and have found them to be excellent. I've found that the Enloops are slightly better at holding voltage when a high load is put on them though.

If you want a really good indicator of how good these batteries are, at last years F3J European Championship over 50% of competitors used Enloops for Rx batteries. These guys aren't going to risk planes worth £1000's on batteries that dont do the job. During launch and landing high peak loads have to be dealt with and Enloops are clearly capable of doing so. Mine certainly hold their charge zillions of times better than standard NiMh's and to date have held capacity over time as well.

I have a 2100mah instant battery in one of my f3f/b models and it is about 2 years old. I recently cycled it and it took about 2050 mah on the cycle, which is basically the same as it was when it was new. It doesn't self discharge very much either.

I know a guy who says that his nimh charger doesn't work properly with instant type batteries, so I guess some people may be having a problem in that regard. 

a guy has had x2 packs fail he thinks over charging
just a thought wall chargers can they over charge instants 
the light on mine will go out when the pack is charged but do some just keep on going
Ron

a guy has had x2 packs fail he thinks over charging
just a thought wall chargers can they over charge instants  
the light on mine will go out when the pack is charged but do some just keep on going
Ron

surely a non peak detect charger can over charge any type of nimh battery. I've never used one to be honest (and never would).

The chap I am talking about though is using a peak detect charger.

I assume you're aware that a fully charged NiMH should not be left on a trickle charge of more than C/300?
(So, for my 2Ah Enloops that's ~7mA!)

I'm flattening them pretty much each time, and use a peak detecting charger to recharge, then take them out (so no trickle charge, I suspect some peak detect chargers do trickle charge after the recharge is complete, who knows what rate!).

Several dozen cycles like that, I haven't done a detailed capacity check on all the cells, but there is no noticable difference in performance levels generally.

Nige

Hi,


Iv`e just had a " Instant " battery loose approx 20% of it`s capacity in 6 months or approx 50 flights. This is the 2100mah version. I have always charged it up using the Supplied Ripmax/Futaba 150mah charger that came with the FF7-2.4ghz TX. I had 3 flights totalling 15 minutes from being fully charged and it was down to 3.9 volts according to the Futaba battery checker. That's when i got some else to check the battery.

I will admit that i do cycle them using my Futaba battery checker @ 1amp. Another club member checked the battery and it`s down to 1800 total capacity.

I think i will change to Eneloop ones instead.

Wisdom seems to be emerging that charging ANY NiMh AA's at lower than 0.5C or higher than 1C can cause damage. lower currents can mean the peak detect doesn't work and overcharging causes damage. Trickle currents as supplied by most radio manufacturers are not just absorbed like we got used to with NiCads, it apparently causes damage.

This then suggests that a charger with a NiMh program that can be set between 05.C and 1C is needed, and that the radio manufacturers need to catch up.

Source - Dec BMFA news P32. Among other sources now forgotten.
Don't know if we should take it as gospel, but food for thought?

just a thought wall chargers can they over charge instants ,
the light on mine will go out when the pack is charged but do some just keep on going
Ron

Ron is yours a Futaba type wall charger?
If so theres no active electronics in there, just a rectifier and ballast a resistor, and the LED with its own series resistor is across the ballast. In the NiCd days the voltage across the ballast was enough to keep the LED lit, but NiMh float to a much higher charge voltage, leaving less across the ballast, hence the LED goes out mid-charge.
That doesnt mean your battery is fully charged, far from it, and it doesnt mean the charger has cut off.
These chargers have not changed much since the early NiCd days and will give a much lower charge current into an NiMh pack because of its higher float voltage and the simple resistive current limiting. Added to that the extra capacity of a typical NiMh (eg Instants @ 2100mah) and you can see that the pack probably isnt getting a full charge unless you leave it on for ages, and when it is finally charged, your charger doesnt cut off (although the LED goes out) and starts to damage the cells. You can confirm all this easily with a meter.
In a nutshell, this type of charger isnt really suitable for high capacity Nimh packs, the only reliable way is a proper peak charger with a discharge facility for occasional capacity tests.
Sorry to waffle on   
Cheers
Phil

I  believe Instants suffer exactly the same from using a wall charger. Again use between 0.5 and 1C.

Another issue apparently is that the higher capacity AA's suffer from having materials so thin that they cant supply decent currents. Materials are made thinner and thinner to get more of them in there for the capacity.

So we could well be better staying with NiMh's below a certain capacity?  Who knows what capacity?  Maybe 2000s are OK but bigger are trouble?   Anyone any thoughts?

Ron is yours a Futaba type wall charger?
If so theres no active electronics in there, just a rectifier and ballast a resistor, and the LED with its own series resistor is across the ballast. In the NiCd days the voltage across the ballast was enough to keep the LED lit, but NiMh float to a much higher charge voltage, leaving less across the ballast, hence the LED goes out mid-charge.
That doesnt mean your battery is fully charged, far from it, and it doesnt mean the charger has cut off.
These chargers have not changed much since the early NiCd days and will give a much lower charge current into an NiMh pack because of its higher float voltage and the simple resistive current limiting. Added to that the extra capacity of a typical NiMh (eg Instants @ 2100mah) and you can see that the pack probably isnt getting a full charge unless you leave it on for ages, and when it is finally charged, your charger doesnt cut off (although the LED goes out) and starts to damage the cells. You can confirm all this easily with a meter.
In a nutshell, this type of charger isnt really suitable for high capacity Nimh packs, the only reliable way is a proper peak charger with a discharge facility for occasional capacity tests.
Sorry to waffle on   
Cheers
Phil

i agree with all of the above my wall charger (hitec) gets used very little my field charger does 90% of the work as i like to see what it has used over x flights more so on a new model then 3-4 times a year a cycle just to make sure its still upto the job
Ron

Hi,


Iv`e just had a " Instant " battery loose approx 20% of it`s capacity in 6 months or approx 50 flights. This is the 2100mah version. I have always charged it up using the Supplied Ripmax/Futaba 150mah charger that came with the FF7-2.4ghz TX. I had 3 flights totalling 15 minutes from being fully charged and it was down to 3.9 volts according to the Futaba battery checker. That's when i got some else to check the battery.

I will admit that i do cycle them using my Futaba battery checker @ 1amp. Another club member checked the battery and it`s down to 1800 total capacity.

I think i will change to Eneloop ones instead.

From past experience selling the Instants the bulk of the problems I hear about are by using trickle chargers that charge at above 100mA. It's all  okay if you can determine exactly how much charge a pack requires but if you can't you either run the risk of undercharging them or overcharging them. If you overcharge them then there is 150mA being pushed into a pack that is already fully charged. This seems to be more energy than the cells can vent off and the result is that they start to overheat, quite possibly for a prolonged period until the charging is stopped. This is nether good for the battery and I would suggest that it could have safety implications too if the battery got very hot.
I always advise to either use a Voltage Peak detect charger or a trickle charger that charges at no more than 80 mA

I believe that any sort of trickle charge can cause damage if left connected beyond full, because cell voltage continues to rise above that which is good for the cells.

I opened this thread with a quote from  an AAA Instant supplier -

''For these cells to keep there ability of storing the capacity for long periods of time, it is best that these cells be cycled not just topped up, When these cells are topped up they loose their ability to store capacity for long periods of time.''

I have used 2100 mA AA Instants for 3 years now and am satisfied with their life span (2-3 years) and their ability to retain charge. I also have gradually reached the conclusion that the best way to charge them is with a peak detection charger at about 0.5 amps.

I do form charge occasionally with 200 mA from 'flat' for 16 hours to re-balance the cells but the only pack I routinely charged with a top up 70 mA trickle, lost capacity and charge retention. It was an 8 cell Tx pack.

i have only one pack that i use for an electronic ignition the only problem i have when they are not used for a while is are they still ok so i treat them as basic cells and top them up to be sure to be sure
or it will be at the back of my mind are they ok
Ron

OK chaps and chappies....


My Futaba 9C has fitted a 2100 mA Vapextech INSTANT pack which is about 12/18 months old.

I charged it with a constant 200 mA and it came off charge with a voltage of 11.6/7 volts. I should say that my friends 9C reads 0.3 volts less than mine, so you really have to understand the value or otherwise of some 'amateur' observations!


So, an 8 cell pack has an nominal voltage of 9.6 V

So, I fly for 3 weeks and find that my TX pack voltage has dropped to 9.9V. Remember a Futaba 9C Tx alarms at 8.3 V

I note that the Tx 'on time' has been 2 hours 9 minutes.

I peak charge the pack and it takes 579 mA ie 28% of capacity has been used, soI have 7+ hours to go before it's very flat.


So, what are my conclusions?

1. Instants are fine go fly.
2. Lipos are fine, go fly, just don't leave the Tx turned on when you get home.
3. I'm sure Sanyo Eneloops are just as good but at twice the price why bother, but go fly in any case?

I really ought to lock my thread but these new LSD discharge NiMh cells are certainly worth a bit of a natter about and some of the very best are as cheap as chips as they say!

The first vapextech instant pack's I bought are great, and work just as described.
So bought 4 more last summer, they were useless, worse than normal NiMH/NiCd packs.
Flat after a couple of weeks, down 50% in a matter of days, so don't live up to the instant claims.
Sadly I didn't test them as soon as they arrived and with only a 30 day warranty was to late to send them back.

That is strange, the reliability of these cells is pretty much accepted now,  so it seems incredible that any one individual should suffer four duff packs.
I wonder if they were "Flat after a couple of weeks, down 50% in a matter of days" whilst fitted in equipment, or on the shelf?
To become flat (from 2A/H) over 2 weeks needs a constant 6ma, thats way higher than could be down to self discharge, so could it be leakage current somewhere within the equipment maybe?
I'm just baffled as to why most are perfect yet someone has such bad luck...
Cheers
Phil

So called 'instant' batteries are just as susceptible to manufacturing foibles as you know with engines  --  you get good manufacturers and bad.   You can get a lemon in engines, autos, electronic equipment, no?

The first vapextech instant pack's I bought are great, and work just as described.
So bought 4 more last summer, they were useless, worse than normal NiMH/NiCd packs.
Flat after a couple of weeks, down 50% in a matter of days, so don't live up to the instant claims.
Sadly I didn't test them as soon as they arrived and with only a 30 day warranty was to late to send them back.

Who did you buy them from as I'm surprised about the 30 day warranty that you mention. Strictly speaking the 30 days is irrelevant as if you buy a product they should be fit for purpose and that means lasting longer than 30 days. the problem with batteries though is that the lifespan of the product is very much determined by what the customer does to it in the form of charging that he uses. It does seem strange that you had four packs that were ALL bad and if I was the person who had sold them I would be suspicious that the charging process was partly to blame for this occurence.

Well I suspect it was a bad batch or maybe damaged during construction/soldering or something. Like I said the previous Tx and Rx packs I bought were and still are fine, great infact.
The suspect ones were "on the shelf", ie not connected to anything.
One was installed in a model but noticed it was low about a month later when I topped it up to go flying.
3 will cycle to their rated capacity, 1 fair a bit lower, but don't hold charge like they are supposed to.
Charging method is same for new and old packs, Pro Peak constellation charger on NiMH program, so think its unlikely since the originals are fine.
2 were charged on the NiMH auto setting and 2 on a NiMH programmed 210 mAH charge rate.
Bought direct, that's where I read the 30 day thing.
Maybe I should of been a bit suspicious when the first of the instant batteries I used was already flat when it arrived, but since the first ones were so good I didn't think much about it at the time.
The other 3 were also flat but that was 2-3 months later, when I got round to using/checking them.

Even after all this time, I'd expect Vapextech to be interested in your story, have you tried contacting them?
Your troubles really are most unusual.
Phil

Grief for me too. I hate them. Fast self discharge, short life span da da da.
I have an electric pepper grinder, they work fine in that.
My Sanyo's and GPs self discharge 50% in a couple of weeks and can only achieve 50-60% of capacity and are only 8 or 9 months old. Ugh.

I'm trying yet another alternative quite simply because I cannot get any other size into two of my models.....So far my AA Instants are all perfect after 2-3 years. We'll see.Steve.

Sorry, Mr Thickie. Whats AA Instants ??

double "A" sized vapex "instant" cells I would imagine.   

"Instants" seems to be a name used for low self discharge NiMH cells (LSD)

Similar to Eneloop by Sanyo, but cheaper.