Future of nimh cells

[Tim Fry]

With Lipo being so popular what is the future for nimh cells? My car only takes cells so where does that leave us?

Thanks

[HBRULEZ]

I won't worry at the moment as Mardave and 12th scale cars run on 4cell (4.8V). As Lipo's are 3.7V per cell (2cell Lipo is 7.4V), you can't really run them in these cars, so the Nimh still have a future in the RC world (for now).

[rharris72]

yes but im sure i have read somewhere that the Japs are testing running on just a single cell lipo voltage not as much as 4 cell nimh but apparently it does work.

[HBRULEZ]

If true then 12th driver will probably have to go back to using receiver packs as most servo run on 4.8V.(don't they?)

[PDW]

LiPo is only used in Bikes and Tc Super Stock. TC Mod, 12th and every other electric class uses NiMh. Added to which is powers all the Oval classes in the USA, and every single class in Japan (LiPo not allowed in Japan).

It isn't as easy to get NiMh as it used to be, so you need to plan in advance and order early. Nonetheless, there are still plenty available, and will be for some years yet. The next big step will be the A123-type cells in a few years time.

Get yourself a good model shop to order stuff for you. I can recommend PBM - Andy will order cells for you, and because he does that they are fresh and good to go. Remember to make sure that the cells are all over 1.0v when you get them, and reject back anything that has no volts - just like LiPo. HTH :)

[jampot]

apparently they are in proccess of developing/testing 2.4 v lipo cells so with this 2 cell equals 4.8 v. I've heard many different things but lipo is not the future there will be something else, lipo is a stepping stone.

[MikeS]

....and who might "they" be then ?

[spmcc]

apparently they are in proccess of developing/testing 2.4 v lipo cells so with this 2 cell equals 4.8 v. I've heard many different things but lipo is not the future there will be something else, lipo is a stepping stone.

"They" Mike are little green men, who in their spare time make crop circles, and abduct people and turn them into 2.4V Lipos.

[MikeS]

:eek::rolleyes::D

[rharris72]

also the a123 cells are out of spec for a sub c cell but another rumour is that a well known company in this country are in talks to try and get them in flat cells which as these are 3.3volts each would mean closer to the 7.2 volts of 6 cell racing and the capabilties of fast charging in like 15mins ?

but i state it is a rumour ???????

[spmcc]

You know what RUMOUR stands for:-

R......Random
U......Unfounded
M.....Meaningless
O.....Or
U.....Useless
R.....Rubbish

:D;):)

[MikeS]

Jeez, if your going to quote me, you could name me :rolleyes:

[spmcc]

But Mike if he did name you, "They" might decend for the plant Rumour and take you away to experiment on. But then again your internal resistance maybe to high.

[MikeS]

[Tim Fry]

Mike what's you're thoughts on the future of nimh?
I ask as buggys tend to use various cell layouts for balance etc

[MikeS]

Wow, thats really a difficut one to answer. Okay, purely from a personal perspective.....no official value at all!

The Sub-C cell package is still used by quite a lot of racers, particularly in those that have 4 cell classes (1/12th, stock cars, Mardaves etc....) and the 5 cell Mod/TC of course. In 4 cell this is really important as they currently do not have an easy to use "alternative" that fits easily into the the chassis or the class, so is likely to remain. The 5 cell Mod/TC is purely down to the membership at the next AGM, and at this point in time I have absolutely no idea on what, if any, proposals may have been submitted that would change this.

Regarding off-road, I can see a move to allow the use of LiPo coming soon......it makes sense as this would not be too difficult to introduce and something a lot of drivers would like to see. Yes there will be a few small issues to address but not as difficult as the 4 cell class presents. I can also see that there will be a rationalisation of the current LiPo list to become the BRCA EB LiPo list rather than just a TC section specific one as it currently is. So some small changes in dimensions and spec would need to be addressed to allow more flexibility in the pack arrangements for the various off-road pack styles, not overcomable, but the LiPo rules will need adjusting to allow this.

Regarding the supply situation on NiMh cells. There are a number of reasons for this to have deteriorated over the last year. The increase in the use of LiPo was always going to be a potential problem for NiMh's, and this HAS been the case. However the bad experiences that the NiMh cells went through didn't help their cause one bit. Also the questionable reliability of the NiMh cells became a major issue for shops stocking cells. This ultimately went right up the supply chain. Because the failure rate of the cells increased so suddenly with cells self-discharging so frequently, to become unusable, this made shops nervous of stocking them, this in turn made the matchers more sensitive to cell volumes they were getting in, and the same for the distributors....... the upshot of this is a general nervousness and lack of stock at the retail facing suppliers who pretty much now stock little or no NiMh's only getting them to order and hoping they will be fresh cells when they arrive! Which in turn sort of pushes people into "trying" out LiPo, if they can, and once they do they rarely go back unless there is a specific reason to do so. With the possible adoption of the off roaders to LiPo packs, then this will only get worse. So the availability of NiMh cells, of any kind is likely to worsen from it's current poor level - when compared to say 2 years ago. I know that the latest NiMh cells are said to be okay, I can't comment as I have not tried and have no interest in doing so. But, I also have no reason to doubt these comments, however once market confidence in a product is lost, it very rarely recovers.........if at all. This sport NEEDS Nimh cells to be available for those classes that HAVE to use them, at least until they have an alternative available, or change their classes to make use of an obtainable alternative.

I will stick my hand up to being one of those that probably have not helped the NiMh situation any, but it was our own experiences with the "latest" NiMh cells that did it. The sudden drop in reliability and high failure rates we were experiencing when matching that pushed me to dropping NiMh cells entirely and returning the whole batch to the manufacturer, and I will say I do not regret it! After a full season of regular use at both National and club levels right across the country there are now large numbers of people who have used LiPo without any problems at all and are very happy with them. So from a technical point of view the approved ones are more than up to the job, the problem lies with the individual classes being actually able to make use them.

While my response is provided objectively, and I hope seen to be that way. I have jumped to the LiPo camp for very good reasons, and for the classes I am directly involved in it has proven to be a HUGE success for all the drivers. However as previously stated, LiPo is not an easily adopted route for ALL classes. Some, with a small change, can use them, but for others the changes required could prove more than possible or acceptable and so will not happen, for this reason we still need a supply of NiMH's cells, but for those that HAVE to have them I fear it could get worse not better.....

[PDW]

Well put Mike. I'd like to add one thing, which I also think is significant. One way of getting good, reliable supply of NiMh is to buy from overseas using the Internet. It seems that other suppliers (in particular the US) are quite capable of supplying NiMh cells on good lead times, fresh, and with good performance.

This is turn leads people to realise that they can get anything like that, which in turn leads them to realise that most of the LiPo cells are also very much cheaper. I wonder if the trade has thought this through well enough. As you say, once something loses its fear (LiPo, or buying from overseas) or reputation (NiMh) it is very difficult to recover.

Whilst I fully appreciate why the trade have decided not to stock NiMh, there are unintended consequences of this action. I hope that this decision does not come back to haunt the trade, as without it (you!) we don't have a hobby worth the name.

[Oliver]

I agree with both Mike and PDW here. This year for the first time I was struggling to get cells, ready for the 12th season. Ended up getting them from the states as I found them at a sensible price for a well-known US manufacturer who had got their shipment through that very week. Cells are something I'd never even considered buying abroad due to weight...... but like Pete says it is something I will have to consider in the future (especially as LiPo are lighter :-D )

Personally, I think the current "standards" for both LiPo and NiMH are in good places to suit RC racing. Just wondering when we get some form of (and I don't really mean A123 or nanotech here) cell that works out to around 6v (ie 5 cell equivellant) will we got to that in all TC classes?? Likewise I am sure that very soon we will have some suitable cells with a suitable votage that will (effectively) replace 4 cell NiMH.

[MikeS]

Thanks Pete/Olli. I hate the break the bubble, but the shipping of LiPo by air is VERY closely monitored and controlled, there are very strict restrictions in place regulating the amount of Lithium allowed with quite large penalties. With most, if not all, air freight being scanned these days it might be harder than you think.

[Mark Christopher]

Well put Mike. I'd like to add one thing, which I also think is significant. One way of getting good, reliable supply of NiMh is to buy from overseas using the Internet. It seems that other suppliers (in particular the US) are quite capable of supplying NiMh cells on good lead times, fresh, and with good performance.

This is turn leads people to realise that they can get anything like that, which in turn leads them to realise that most of the LiPo cells are also very much cheaper. I wonder if the trade has thought this through well enough. As you say, once something loses its fear (LiPo, or buying from overseas) or reputation (NiMh) it is very difficult to recover.

Whilst I fully appreciate why the trade have decided not to stock NiMh, there are unintended consequences of this action. I hope that this decision does not come back to haunt the trade, as without it (you!) we don't have a hobby worth the name.


pete please read the rules re buying over seas and rcracechats stance on the issue (rule 7)

[Mark Christopher]

I agree with both Mike and PDW here. This year for the first time I was struggling to get cells, ready for the 12th season. Ended up getting them from the states as I found them at a sensible price for a well-known US manufacturer who had got their shipment through that very week. Cells are something I'd never even considered buying abroad due to weight...... but like Pete says it is something I will have to consider in the future (especially as LiPo are lighter :-D )

Personally, I think the current "standards" for both LiPo and NiMH are in good places to suit RC racing. Just wondering when we get some form of (and I don't really mean A123 or nanotech here) cell that works out to around 6v (ie 5 cell equivellant) will we got to that in all TC classes?? Likewise I am sure that very soon we will have some suitable cells with a suitable votage that will (effectively) replace 4 cell NiMH.


as above oli please

[PDW]

pete please read the rules re buying over seas and rcracechats stance on the issue (rule 7)Mark, point taken. I hope that the trade will consider the point, too.

[Mark Christopher]

Mark, point taken. I hope that the trade will consider the point, too.

cheers pete, maybe those effected should all contact said distributors?

[Steve Cann]

maybe those effected should all contact said distributors?



They'll either do as already indicated...

Or worse still see it as final nail in coffin and seek their "good day out" elsewhere :(...


What puzzles me is that the Li-Po 'list' which ostensibly only concerns about 100 has gained a good number of submissions yet the motor 'list' for the same 100 has seen relatively speaking very little interest from 'the trade'...

[PDW]

We're wandering a bit off topic, but...

The reason no one is bothering to make 10.5 to our Rules is that BL is not legal in Japan (from whom most of the Far East take their lead) and that ROAR has declared it's Stock and Spec classes to be 17.5 and 13.5 respectively. There is no incentive for any manufacturer to make thee motors to our Rules, when the biggest market is in the US and it is for different wind motors - and I think the ROAR Rules are less onerous. One look at the ROAR list shows all the manufacturers that people want to use having 13.5 and 17.5 motors approved by ROAR, but not on our 10.5 list. In 12th, the reality is that a 10.5BL motor is only a smidge slower than a 12T brushed. ROAR's decision to take the chance (with the BL introduction) to slow it all down seems to have worked - US forums are chock full of advice being sought for these winds. For 100-odd drivers, I wouldn't, as a supplier, bother to make and homologate a special motor for the UK, and that's why I think they have only three motors on their list.

The NiMh issue is easily resolved, but it means that the trade has to change its business model in regard to its supply chain. Recognising that cells need to be fresh, the supply chain has to change to ensure that an order from a shop is fulfilled direct from the 'factory' in minimum time, thus allowing the shopper to get a 2 to 3-day delivery. Yes, it might cost more, but with so many people gagging to pay almost twice the price for their cells by going LiPo, and with the Orion and EnerG/GP cells being back to what we used to have, why wouldn't this work?

I don't think it's come to seeking thrills elsewhere because of the cells, people will work around that (unless the trade changes its supply chain), but the current economic situation is another matter altogether...

Back on topic in the end! ;)