295LikesTamiya mini cooper
04-21-2009 | 03:42 PM
#8914
These new LF batteries are cutting edge technology. I'm pretty stoked about them even though their capacity is a little low. The voltage is a little low for our application, but nothing that can't be fixed with brushless or a hotter motor. 6.6V batteries could be just the ticket for 1/12 scale... Apparently A123 developed them in conjunction with MIT. A few of the major Chinese battery manufacturers are spooling up production this month as well. I'm kicking around using these for a 1:1 EV project later this year.
04-21-2009 | 06:13 PM
#8915
Tech Elite
Joined: Aug 2001
Posts: 2,583
These new LF batteries are cutting edge technology. I'm pretty stoked about them even though their capacity is a little low. The voltage is a little low for our application, but nothing that can't be fixed with brushless or a hotter motor. 6.6V batteries could be just the ticket for 1/12 scale... Apparently A123 developed them in conjunction with MIT. A few of the major Chinese battery manufacturers are spooling up production this month as well. I'm kicking around using these for a 1:1 EV project later this year.
Can't wait for aaa sized batts. 2 cell Awd pan for the "other" mini.
04-21-2009 | 08:26 PM
#8917
Tech Elite
Joined: Aug 2001
Posts: 2,583
04-21-2009 | 08:29 PM
#8918
I only heard a quick blurb about them on the news the other day. They're extremely stable, charge quickly (VERY high charge rate) and won't go all explody if you punch a nail through them.
From what I heard they're some sort of lithium/titanium thing. If I find out more, I'll post it.
EDIT: Sorry, it's Toshiba and the cathode is a lithium-titanate. Reduced capacity, but super fast charging. The following text was "borrowed" from businessgreen.com.
"Toshiba has improved it's Super Charge Ion Battery technology to the point where a 90 second recharge is possible. With enough amperage it would actually be faster to recharge than to fill up with gas.
What we call "Lithium Ion" batteries these days are actually using a lithium-cobalt cathode acting against a graphite anode in most circumstances. They work great for high density energy needs but suffer from somewhat sluggish charge times, reduced power capacity over successive charges and the nasty habit of blowing up when things go bad. Toshiba's SCiB batteries use a lithium titanate-based cathode which unfortunately reduces energy density, but achieves significantly faster charge times and suffers much less capacity degradation over time. It's also completely inert compared to lithium cobalt batteries — you can drive a nail through a cell and it doesn't care. The initial versions charged in about five minutes but Toshiba has announced improvements which slashes charge time down to 90 seconds per cell.
Cell charging times are multiplied over the entire battery pack, so the total charging time is dependant on how many cells are involved. However, the capability to charge in such short times still exists, so achieving a super short charge time is possible with a big enough power supply. We're talking organ liquefying amperage, but the danger could certainly be mitigated as it is with today's charging systems. Toshiba is talking about aiming the technology at EV bikes, motorcycles and hybrids.
Charge time is our primary barrier to being head over heels about electric cars. If we can get recharging to look more like refueling we'd be all over some zero-emissions, instant-torque, high-RPM action."
Jim
From what I heard they're some sort of lithium/titanium thing. If I find out more, I'll post it.
EDIT: Sorry, it's Toshiba and the cathode is a lithium-titanate. Reduced capacity, but super fast charging. The following text was "borrowed" from businessgreen.com.
"Toshiba has improved it's Super Charge Ion Battery technology to the point where a 90 second recharge is possible. With enough amperage it would actually be faster to recharge than to fill up with gas.
What we call "Lithium Ion" batteries these days are actually using a lithium-cobalt cathode acting against a graphite anode in most circumstances. They work great for high density energy needs but suffer from somewhat sluggish charge times, reduced power capacity over successive charges and the nasty habit of blowing up when things go bad. Toshiba's SCiB batteries use a lithium titanate-based cathode which unfortunately reduces energy density, but achieves significantly faster charge times and suffers much less capacity degradation over time. It's also completely inert compared to lithium cobalt batteries — you can drive a nail through a cell and it doesn't care. The initial versions charged in about five minutes but Toshiba has announced improvements which slashes charge time down to 90 seconds per cell.
Cell charging times are multiplied over the entire battery pack, so the total charging time is dependant on how many cells are involved. However, the capability to charge in such short times still exists, so achieving a super short charge time is possible with a big enough power supply. We're talking organ liquefying amperage, but the danger could certainly be mitigated as it is with today's charging systems. Toshiba is talking about aiming the technology at EV bikes, motorcycles and hybrids.
Charge time is our primary barrier to being head over heels about electric cars. If we can get recharging to look more like refueling we'd be all over some zero-emissions, instant-torque, high-RPM action."
Jim
Last edited by monkeyracing; 04-21-2009 at 08:46 PM.
04-21-2009 | 09:08 PM
#8919
I only heard a quick blurb about them on the news the other day. They're extremely stable, charge quickly (VERY high charge rate) and won't go all explody if you punch a nail through them.
From what I heard they're some sort of lithium/titanium thing. If I find out more, I'll post it.
EDIT: Sorry, it's Toshiba and the cathode is a lithium-titanate. Reduced capacity, but super fast charging. The following text was "borrowed" from businessgreen.com.
"Toshiba has improved it's Super Charge Ion Battery technology to the point where a 90 second recharge is possible. With enough amperage it would actually be faster to recharge than to fill up with gas.
What we call "Lithium Ion" batteries these days are actually using a lithium-cobalt cathode acting against a graphite anode in most circumstances. They work great for high density energy needs but suffer from somewhat sluggish charge times, reduced power capacity over successive charges and the nasty habit of blowing up when things go bad. Toshiba's SCiB batteries use a lithium titanate-based cathode which unfortunately reduces energy density, but achieves significantly faster charge times and suffers much less capacity degradation over time. It's also completely inert compared to lithium cobalt batteries — you can drive a nail through a cell and it doesn't care. The initial versions charged in about five minutes but Toshiba has announced improvements which slashes charge time down to 90 seconds per cell.
Cell charging times are multiplied over the entire battery pack, so the total charging time is dependant on how many cells are involved. However, the capability to charge in such short times still exists, so achieving a super short charge time is possible with a big enough power supply. We're talking organ liquefying amperage, but the danger could certainly be mitigated as it is with today's charging systems. Toshiba is talking about aiming the technology at EV bikes, motorcycles and hybrids.
Charge time is our primary barrier to being head over heels about electric cars. If we can get recharging to look more like refueling we'd be all over some zero-emissions, instant-torque, high-RPM action."
Jim
From what I heard they're some sort of lithium/titanium thing. If I find out more, I'll post it.
EDIT: Sorry, it's Toshiba and the cathode is a lithium-titanate. Reduced capacity, but super fast charging. The following text was "borrowed" from businessgreen.com.
"Toshiba has improved it's Super Charge Ion Battery technology to the point where a 90 second recharge is possible. With enough amperage it would actually be faster to recharge than to fill up with gas.
What we call "Lithium Ion" batteries these days are actually using a lithium-cobalt cathode acting against a graphite anode in most circumstances. They work great for high density energy needs but suffer from somewhat sluggish charge times, reduced power capacity over successive charges and the nasty habit of blowing up when things go bad. Toshiba's SCiB batteries use a lithium titanate-based cathode which unfortunately reduces energy density, but achieves significantly faster charge times and suffers much less capacity degradation over time. It's also completely inert compared to lithium cobalt batteries — you can drive a nail through a cell and it doesn't care. The initial versions charged in about five minutes but Toshiba has announced improvements which slashes charge time down to 90 seconds per cell.
Cell charging times are multiplied over the entire battery pack, so the total charging time is dependant on how many cells are involved. However, the capability to charge in such short times still exists, so achieving a super short charge time is possible with a big enough power supply. We're talking organ liquefying amperage, but the danger could certainly be mitigated as it is with today's charging systems. Toshiba is talking about aiming the technology at EV bikes, motorcycles and hybrids.
Charge time is our primary barrier to being head over heels about electric cars. If we can get recharging to look more like refueling we'd be all over some zero-emissions, instant-torque, high-RPM action."
Jim
thanks for the info...
04-22-2009 | 04:47 AM
#8921
diff
Hey guys,
Great thread, I read most of it when I first got M03 Cooper few months ago.
Our racing season indoors is over. I get to race it now only sporadically.
I tried ideas I found in this thread about limiting diffs unloading. I come up with one which worked for me for over a month thats at least 5 race days.
Instead off using shims on outside of large bevel gears I sandwiched tiny o-ring in between shims. Shims are only 0.2 mm thick and o-ring is 0.4 mm. Total of 4 shims and 2 o-rings plus silicone grease. Diff works smooth, but it has a little drag to it. When you spin one wheel by hand, you will spin motor.
Rob
Great thread, I read most of it when I first got M03 Cooper few months ago.
Our racing season indoors is over. I get to race it now only sporadically.
I tried ideas I found in this thread about limiting diffs unloading. I come up with one which worked for me for over a month thats at least 5 race days.
Instead off using shims on outside of large bevel gears I sandwiched tiny o-ring in between shims. Shims are only 0.2 mm thick and o-ring is 0.4 mm. Total of 4 shims and 2 o-rings plus silicone grease. Diff works smooth, but it has a little drag to it. When you spin one wheel by hand, you will spin motor.
Rob
04-22-2009 | 06:56 AM
#8922
So...you're putting the o-ring between the shim and the diff case, or between the shim and the bevel gear? What is the diameter of the shim you are using?
I'd love to know this stuff as I'm constantly messing around with gear diffs trying to get smooth action with a little lock up.
Thanks!
Jim
I'd love to know this stuff as I'm constantly messing around with gear diffs trying to get smooth action with a little lock up.
Thanks!
Jim
04-22-2009 | 12:29 PM
#8925
I doubt anything that would only fit in the Stampeded would fit in the M03. The M03 is supertight in the battery compartment. Keep in mind that A123 is a pretty huge battery manufacturer, so I'm thinking the battery you are talking about is different altogether. Maybe a 3s lipo? Also the lithium iron phosphate chemistry was just recently announced, so I'd be surprised if it was around earlier. Honestly, I'm incredibly surprised that this is out so soon in the R/C market! MIT and A123 just went public on this technology only 1 month ago!