[RIPPERTON]

Originally Posted by jonescg

That's pretty lousy service! Be careful of sending them back - it will end up costing you a lot more than it should.

Worse comes to worst, you can spot weld copper tabs to them to make them longer, but I'm sure you have better things to do than fold up 800 bits of copper.

I can solder a pack up for you for round three if you like

See you next week Dan!

Chris

They are paying for postage both ways.
Thanks but I wouldnt have a soldered pack, I dont believe in soldering or having an unventilated pack even if they are A grade low IR cells.
The current pack will do QLD even if the races are almost twice as long as Wakefield. 8.8km - 15.5km

[jonescg]

Originally Posted by RIPPERTON

They are paying for postage both ways.
Thanks but I wouldnt have a soldered pack, I dont believe in soldering or having an unventilated pack even if they are A grade low IR cells.
The current pack will do QLD even if the races are almost twice as long as Wakefield. 8.8km - 15.5km

Good to hear they are acknowledging the cock-up. Hope it goes smoothly for you.

My pack will be vented, but not for active cooling. More like an emergency release valve And they will point downwards for good measure. I'm embedding a couple of thermocouples in there to warn me of any impending disasters. Anyway, if the solder is getting hot enough to melt, you got bigger underlying design problems.

Good thing about the old pack is that you can run it into the ground for QR and have a shiny new pack ready for Wackyfield. Andy might get to film some more smoke!

[evmotorcycle]

That's a total bummer man. You have been waiting so long for these to arrive as well. Now you are really testing the longevity of those LiPo cells. Let's hope the old ones do the business for Queensland.

[RIPPERTON]

Of course my relentless God given design computer has fashioned a solution to the short tab issue.

Ive been working on a better simpler design technique for capturing the cells and the short tabs forced me to come up with something new.

The only bitch is that if I was going to make a new frame design I would have ordered 6Ah cells because they are cheaper by the kWh and would need less of them making it even simpler again.

I only ordered 4Ah cells so I could put them straight into the existing frame and even some of the older frames.

Looks like YGS are going into the DIY bad books unfortunately in particular "Apple" the sales idiot who systematically botched everything in the name of raking in money $$$$$. Then the other half of the problem, the so called engineer who took 3 weeks to box the defective short tabbed cells that they had lying around in stock for the economy of getting rid of them.
They actually told me the "custom long tab cells" would take 3 weeks to make special order.

The 9mm tabs are even shorter than the standard length tabs they have which is 15mm, so these really are defective cells that they couldnt get rid of.

[RIPPERTON]

Originally Posted by jonescg

My pack will be vented, but not for active cooling. More like an emergency release valve And they will point downwards for good measure. I'm embedding a couple of thermocouples in there to warn me of any impending disasters. Anyway, if the solder is getting hot enough to melt, you got bigger underlying design problems.

Its not the melting of the solder that I think is a problem, theres nothing in there hot enough to melt solder anyway. It s the difficulty of replacing a cell that eliminates soldering as an option.

As for ventilation, even low IR cells are going to get warm and if you have 400 cells backed up together like that you might not get that heat out before the next time you go on track and you are going to get an escalation during the day.
A ventilated pack gets any heat out straight away and you can run it full pace as soon as you charge which is 1.5 hours.
Think about it Chris can you get that heat out of the core in 1.5h ?
I would never take a risk with LiPo's especially if it only costs me 80mm of pack height. It still fits in the bike.

[jonescg]

Originally Posted by RIPPERTON

Its not the melting of the solder that I think is a problem, theres nothing in there hot enough to melt solder anyway. It s the difficulty of replacing a cell that eliminates soldering as an option.

It's not that bad. I have gotten quite proficient at soldering with a 200 W iron now.

Originally Posted by RIPPERTON

As for ventilation, even low IR cells are going to get warm and if you have 400 cells backed up together like that you might not get that heat out before the next time you go on track and you are going to get an escalation during the day.
A ventilated pack gets any heat out straight away and you can run it full pace as soon as you charge which is 1.5 hours.
Think about it Chris can you get that heat out of the core in 1.5h ?
I would never take a risk with LiPo's especially if it only costs me 80mm of pack height. It still fits in the bike.

A bit of warmth is good for these cells. I will be draining no more than 20C bursts from these cells at the absolute worst, and even 10C constant drain (150 amps) for 7 minutes only just started to warm them up. 10C on this pack will be 96 kW! Personally I would rather be able to ride this bike in the rain (and not crash ) and know it won't short or fail.

I am trying to get it so charging outside the bike is easy, but I will still need a hoist to get the pack out.

[RIPPERTON]

Awesome weekend racing at Willowbank, same results as Wakefield.
I got 1st on Saturday Jason won on Sunday and I ended up with fastest lap record for an electric bike. 1,32.3. 0.2 seconds faster than Jason.
A comedy of miscommunications left Saturdays race at 5 laps even after I recommended to officials I should do 4 laps due to my battery pack being old.
So we unwittingly raced for 5 laps but my pack handled it no problem.
Catavolt on the other hand didnt handle the 5 lapper as its controller cut out at the end of lap 4 due to the windings overheating.
This let me catch up and overtake to do the last lap in the lead even though I ran of the track through the mud on lap 3.
What was I doing in second you ask ?. I got mugged at the start because My motor is still too small and controller cuts out if the motor is overloaded resulting in slow acceleration.
My bike has a faster top speed and is faster into corners but Catavolt is faster out of corners
So I figured theres nothing wrong with my pack and was looking forward to doing another 5 lapper on Sunday but the original 4 lap request finaly filtered through the cluttered communication system and we were informed only on the grid that it would be a 4 lapper.
I spewed as Catavolt had implicated its water mist cooling system and could now probably do 4 laps without overheating.
Sure enough I got left at the start and Catavolt managed to win even though it started to cut out over the finish line. I was pushing hard and my controller cut out 4 times during the race.
During the post race interview, Catavolt stood in a puddle of water leaking out of its hub on the pit lane. Notions of protests lurked in my mind but didnt bother.
Now Jason and I are dead equal on point and whoever wins on Sunday at the next round in Wakefield takes the championship.
Im finaly going to build the twin motor now as it my only weak point.
Pics and videos later

[RIPPERTON]

The only left hander at Willowbank.

[RIPPERTON]

Water Mist cooling... doesnt work

[Catavolt]

LOL , The mist system does seem to work but is only a temporary measure , At the end of the race we dump the remaining water through the motor to help protect the magnets as this shot shows in the pits.
We are working on a closed loop liquid cooled system for next season.
It seems that we overworked the motor more than we needed in the last races having a 6 and 8 second lead at some stages.