A123 bankrupt - time to look at LiPo's for Heavies

[Kenny]

I think its defiantly a good time to look at this not only with the A123's supply running out but also the biggest event for heavyweights is this weekend, maybe we can have a sit down on the saturday night and have a talk about the pro's and cons of what people think

[kane]

This is something that has been discussed repeatedly for several years now. The whole purpose of the trial is to prove the technology is safe for use in heavyweights. If it isn't then it is unlikely to go any further. If it is, and so far no issues have been raised, the rules will be revised at the end of the trial and draft put out for member approval.

[leorcc]

I suspect Bullfrog doesn't show up that issue as it won't push the cells hard.

The reason they don't get pushed hard is that we just look at what the robot actually would use for a fight and then make sure we are at least on more than that capacity preferably double. As far as the other brand LiFePO4 is concerned, I have not felt any degradation in performance throughout the event. If anything, these cells hold their balance better than the A123's do.

Big Nipper has been allowed to run LiPo's for a reason, to learn - would be good to share the learning and start to formulate rules to ensure the safe use of them.

I agree, though as someone who has been using LiPo for over 6 years in other disciplines I would be very surprised if the outcome of the test is anything but With sensible precautions there is no reason not to allow LiPo.

[maddox10]

When I spoke with Graeme when he popped over to my university he said that everything was going fine but that they had needed to make a pair of unibody 5mm Alu cases for the Lipos.

To contain the flames of a bursting LiPo you don't need 5mm ali, a fine steel mesh is enough, as a Davy lamp proves for almost 2 centuries now.
Or the modern equivalent, a LiPo bag or a piece of a fire blanket.
The more annoying white clouds a burst LiPo spreads can be dealt with a sturdy fan and some flexible tubing like this.

I am not sure what this means for weight but it may be that the safety features required for lipo's may make them almost as heavy as NiCads or SLA's.
The only advantages I can see would be a size reduction and an increase in maximum discharge.
Just a thought...

Cheaper than high end SLA's too.

[terry]

Let's just have a few beers in the pub and agree they are ok ! Job done
A few rules though to be safe .

[teamstorm]

I'm not sure that we need to view this as a serial process where by we trial, then think, then implement. Having checked out the FRA mins, they say pretty much what I thought they did

3. LiPo Trials

Following sucessful use of LiPo batteries in featherweights a trial of the batteries in heavyweights is being carried out by the Big Nipper team. Due to the inherent dangers of the technology the trials will be closely monitored for review at the year end.

Perhaps we could get some feedback as to the 'close monitoring' referenced and what that monitoring has been, what data/information has been collected (I presume against whatever the agreed success criteria were for the trial ?) - maybe we can as Kenny suggests get a working group together to start to understand what might be required as guidelines for LiPos.

If we learn new things from the trial as time goes by, that can be fed into whatever is being developed - but it seems that an old fashioned approach of doing everything in a totally serial fashion will only drag something out that the FRA has the opportunity to be proactive in. Then when the trial ends, we've already got a solid skeleton of some guidance for temas.

Could I suggest that rather than Saturday evening (when we'll be in the pub) a small working group agree to meet at say 4pm on Saturday. Given the trial is due to end at the end of the year, it doesn't seem unreasonable to start to try to crystalise some thinking on what the guidelines might look like.

... and if all those things that I suggested should be there as part of the trial aren't; we can use that group to understand what we should be looking to get out of the trial - as I assume the 'close monitoring' doesn't just mean we get to the end of a non-determined period and go well that seemed to work ok lol

A great opportunity for some progress - who's up for a discussion at 4pm on Saturday ?

[terry]

yep.

[blazerbotics]

Can I suggest we do it Sunday morning around 10.30am, Saturday may be very busy with sorting robots out etc, and i don't know at what point I will be done with the arena.

[teamstorm]

Sure Alan if that works better for you !

[widow_twanky]

Like any new technology safety is paramount. LiPos have demonstrated stable operation but only over a limited timescale. The trial in heavyweights only starting in March after all!

Full details will be released once the trials have been completed.

Kane,

I have to say I disagree with you on this one. Lipos have been used in feathers for a long time. Most of the lipos are as big of those wich would be used in heavies and they have to stand up to the impact of spinners. Big Nipper have been using them without major incident and our colleagues across the pond have been using them with a few incidents none of which i believe have resulted in shows being major well prepared shows being stopped or in injury.

We know two things:

1) Most of the time they can be used safely
2) What they do when things go wrong

I simply cannot understand what the issue is. Surely it's a case of looking at how any safety issues are addressed. I can disagree with Mario et al about what the safety issues are, how serious they are and how much provision should be made for them but surely we should just stop faffing around and deal with the issues surrounding them? We don't need a prolongued test to tell us what we already know.

Andy