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View Full Version : Why are Lipo's so expensive?


JimClark
11-14-2005, 09:48 PM
Just wondering why the larger cacacity cells are real expensive compared to NIMH cells. Is the manufacturing process way more complex?

Jim

ForestCam
11-14-2005, 09:55 PM
New technology for the R/C market so that makes them expensive but the prices are coming down.

I can remember my dad paying in excess of $40 for abig ol' 7.2v nicad stick back in the early 90's and look at what the prices of those are now.

sailr
11-15-2005, 01:51 PM
Just wondering why the larger cacacity cells are real expensive compared to NIMH cells. Is the manufacturing process way more complex?

Jim

Li-Po cells use volatile and expensive materials. The cost of the materials has risen due to greater demand and short supply rather than falling because of volume.
Nicad and NiMh cells have been around for many years and are produced in huge volumes. Lithium polymers are getting there but only in the very small batteries used in cell phones, etc. Small production runs of larger lithium cells of course drives the price up. A final consideration is the handling concerns of lipos. I'm sure you've heard of the explosions and fires from mishandled lithiums! Work conditions in the manufacturing process must be closely monitored for safety.

Our Lithium Polymer batteries help minimize the dangers by using circuit board connections rather than being soldered directly to the battery tabs. This also increases the cost somewhat.

You can buy cheaper lipos on ebay and other outlets but buyer beware. Most of them are of questionable quality and stability. Stay with name brand proven products when using lithiums.

Testing of our batteries shows that they produce, at a minimum, the advertised mAh while the top selling lithium polymer batteries are actually only putting out about 85% of their advertised capacity. We will be posting a lot of lab controlled verified test results on our web site ( www.flyhurricane.com (http://www.flyhurricane.com) ) in the future.

Sincerely,
Jim Slaughter
President
Hurricane Flight Systems

bz1mcr
11-15-2005, 03:12 PM
Supply and demand. The materials costs are way less than 5% of the current selling prices. Manufacturing cost is low and profits are high. That is why prices are coming down as more manufactures get in.

Matt Kirsch
11-15-2005, 04:06 PM
Supply, demand AND liability concerns... Somebody's gotta pay the insurance company just in case, you know.

Hotshot Charlie
11-15-2005, 05:40 PM
New Technology, Supply, Demand.

GeraldRosebery
11-17-2005, 07:57 PM
New technology for the R/C market so that makes them expensive but the prices are coming down.

I can remember my dad paying in excess of $40 for abig ol' 7.2v nicad stick back in the early 90's and look at what the prices of those are now.

Unless you haven't looked lately, decent 7.2V packs - 6-cells are still $35-60.

GeraldRosebery
11-17-2005, 08:09 PM
Just wondering why the larger cacacity cells are real expensive compared to NIMH cells. Is the manufacturing process way more complex?

Jim

That is actually quite a good question that has multiple answers. NiMH SC cells have a huge installed use base from power tools on up to hybrid cars. That drives a manufacturing base that has most of the kinks worked out. Costs are therefore spread over a huge supply. Raw materials are not cheap for either NiMH or NiCd cells so that is why costs are still $5-$8 per cell. LiPo are new and manufacturing failure rates remain stubbornly high. In most facilities each and every cell is checked. Also, high capcity cells are made in (relatively) small quantities (so far) so costs of the plant must be amortized over a smaller volume driving up the unit price. Add to that complex distribution and retail prices remain high. Just like HDTV's a couple of years ago when something is new, people are also willing to pay more. Prices of LiPos are edging down, but don't expect a price collapse. One of the issues is that larger electric planes and motors are being made available and these require ever bigger packs. So per airplane costs are often going up, not down, but that the consumer's choice.

JimClark
11-17-2005, 09:31 PM
unfortunately it is only the bigger packs I have a need for

jim

Unless you haven't looked lately, decent 7.2V packs - 6-cells are still $35-60.

Solcat
11-17-2005, 11:29 PM
www.truerc.com (http://www.truerc.com) custom packs.

Fred Marks
11-18-2005, 03:46 AM
Just wondering why the larger cacacity cells are real expensive compared to NIMH cells. Is the manufacturing process way more complex?

Jim


Jim,

Expensive is relative. Please look over
(http://www.wattflyer.com/forums/showthread.php?t=2490)

Check out the life cycle of 2000 mAh Ni Mh when run continuously at 17.5 amps. The cost for the KOK 2000 with life cycle of 452 cycles is $0.18.flight. Ni MH / flight? Glow fuel: $1.35/flight.

GeraldRosebery
11-19-2005, 10:25 PM
Jim,

Expensive is relative. Please look over
(http://www.wattflyer.com/forums/showthread.php?t=2490)

Check out the life cycle of 2000 mAh Ni Mh when run continuously at 17.5 amps. The cost for the KOK 2000 with life cycle of 452 cycles is $0.18.flight. Ni MH / flight? Glow fuel: $1.35/flight.

If everything is perfect and you never ever screw up, you MAY get 452 cycles from a LiPo (as they did under lab, not flying conditions) From what I read here real life in the field seems to be much shorter than that, sometimes only 50-70 cycles. That can make big LIPo's very expensive per flight and they have a HUGE up front cost. If we could fork out $0.20 per flight as we go, they would be a steal, but we can't. Look at my 17 lb OPUS 782. LiPo's $720/452 = $1.59 / flight. If they last only 70 cycles = $720/70 = $10.28/flight - (OUCH!) Gas - about $0.30/flight (gas at $3/gallon) NiMH ??? I don't know, but since I am using them in the OPUS, I shall eventually find out. I shall let everyone know when they crap out.

Fred Marks
11-19-2005, 10:52 PM
If everything is perfect and you never ever screw up, you MAY get 452 cycles from a LiPo (as they did under lab, not flying conditions) From what I read here real life in the field seems to be much shorter than that, sometimes only 50-70 cycles. That can make big LIPo's very expensive per flight and they have a HUGE up front cost. If we could fork out $0.20 per flight as we go, they would be a steal, but we can't. Look at my 17 lb OPUS 782. LiPo's $720/452 = $1.59 / flight. If they last only 70 cycles = $720/70 = $10.28/flight - (OUCH!) Gas - about $0.30/flight (gas at $3/gallon) NiMH ??? I don't know, but since I am using them in the OPUS, I shall eventually find out. I shall let everyone know when they crap out.

"Screwing up" is relative too! The packs that are reaching only 60 cycles are being operated (driven) too hard (which means the pack was not sized using LIPOCALC II) , are reaching 160 Deg F or more, are not being balance charged, and are being run into the "zone of temptation" that puts the weakest cell below 2.5V. Rough handling can also shorten life. We think the positive experience of several thousand users carries a lot of weight.

The point we are making is that, if you do the things we suggest and you use the FMA systems, then you can expect much greater life cycle as shown by the tests. In fact, if you use IMPAD to protect the pack from hangar rash, charge and discharge with the FMA BalancePro systems, cool the pack before charging, and do not crash the pack, thre is absolutely no reason that the 450 cycles can not be met or bettered in the field.

There are two important facts here: The pack was charged on every cycle at 3C and the BalancePro 6S charger brought each cell to within 5 millivolts of 4.2V on every charge, even the 452 nd charge. These are the things that help bring long life. It is doubtful that many people would ever fly a pack 450 flights as new generation packs arrive and most will replace them before end of life. That simply does not happen with non-balance charging and unbalance can end pack life very early.

As a point of personal experience: My original KOK 3270 first gen pack has lived for almost four years even though it was deliberatly abused. Keith Shaw told me recently that his original home-built KOK 3000 pack had finally died after 396 flights and three years. RD Blakeslee bought the original KOK 3270 cells to build his own packs and has used parallel charging all along. He reports that the pack just died after three years. Tests of the FMA Scorpion pack at "punch " current of 120 amps and average current of 38 amps ran 600 cycles. Remember that the new generation FMA BalamcePro systems make Li Pos a whole new world where life cycle cost goes down to pennies. I certainly think that you can work at it just a little bit and beat Gerald's 60 cycles many times over. Start out by reading the Li Po Handbook at http://www.fmadirect.com/tech_data/techdocs/

so I don't have to repeat all that good stuff here.

Jspencer
11-21-2005, 03:15 PM
Our Lithium Polymer batteries help minimize the dangers by using circuit board connections rather than being soldered directly to the battery tabs. This also increases the cost somewhat.

You can buy cheaper lipos on ebay and other outlets but buyer beware. Most of them are of questionable quality and stability. Stay with name brand proven products when using lithiums.

Testing of our batteries shows that they produce, at a minimum, the advertised mAh while the top selling lithium polymer batteries are actually only putting out about 85% of their advertised capacity. We will be posting a lot of lab controlled verified test results on our web site ( www.flyhurricane.com (http://www.flyhurricane.com) ) in the future.

Sincerely,
Jim Slaughter
President
Hurricane Flight Systems


The reason Lipo prices are so high is because of the cost of advertising them on internet chat groups *cough,cough*.;) :rolleyes: