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Old 01-12-2006, 08:05 PM   #91
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Hello Mr. Hohwart,
I read the FAQ on Orions website and it answered alot on my questions. But I have one question, and one non-experienced one. How long do the packs typically take to charge ? My other is the cut off (recommended 3.0 volts)? I have never checked the voltage of my 6 cell packs when my batts dump. When the LiPo dumps is there a margin of safety before reaching 2.7v and the irreversable damage that could occur as stated? Sorry if it has been addressed; thanks so much.
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Old 01-12-2006, 08:25 PM   #92
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Originally Posted by Rick Hohwart
No problem. I will continue to watch this thread in case there are further questions. And we are happy to take phone calls regardiing the Platinum if anyone feels they need more in depth information.
Rick,
I have 2 of the Platinum packs and so far so good. If and when the time comes, how do I use the balancing/equilizing port on the bottom of the pack?
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Old 01-13-2006, 05:03 AM   #93
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Originally Posted by asw7576
Tex1 has nice topic there...... let me calculate mine according to my needs :

NIMH
IB4200 $60.00 x 3 cells = $180 ---> ( not sure, I heard is even lower )
GFX charger $380 x 2 = $760
Novak Smart Tray $90
Total Cost = $1,030.

LIPO
Platinum Lipo $135 x 3 cells = $405
Advantage Charger $180 x 2 = $360
Total Cost = $765

Hmmm..... not bad, right ?
yes i think so but i think you all forgot to add up the Power Supply
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Old 01-13-2006, 06:35 AM   #94
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Originally Posted by jw92656
Hello Mr. Hohwart,
I read the FAQ on Orions website and it answered alot on my questions. But I have one question, and one non-experienced one. How long do the packs typically take to charge ? My other is the cut off (recommended 3.0 volts)? I have never checked the voltage of my 6 cell packs when my batts dump. When the LiPo dumps is there a margin of safety before reaching 2.7v and the irreversable damage that could occur as stated? Sorry if it has been addressed; thanks so much.
Rick will confirm, but from what I know when you feel that your car becomes soft when you accelerate then it is time to stop. It is very easy to see !
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Old 01-13-2006, 08:04 AM   #95
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Originally Posted by jw92656
Hello Mr. Hohwart,
I read the FAQ on Orions website and it answered alot on my questions. But I have one question, and one non-experienced one. How long do the packs typically take to charge ? My other is the cut off (recommended 3.0 volts)? I have never checked the voltage of my 6 cell packs when my batts dump. When the LiPo dumps is there a margin of safety before reaching 2.7v and the irreversable damage that could occur as stated? Sorry if it has been addressed; thanks so much.
At 4.8 amps it can take about an hour to charge to full capacity. Of course charge time depends upon the starting point of the pack.

Six volts is the lowest voltage you want to safely take your pack to. For reference, a car will stop moving when it gets near 5.4 volts. Our recommendation is that you stop driving the car when it starts to slow. And if you drive it to this point, place it on your charger immediately for a few minutes, then unplug it so that there is no chance that your electronics or cooling fans discharge the battery to unsafe levels.

Quote:
Originally Posted by MADHAT
Rick,
I have 2 of the Platinum packs and so far so good. If and when the time comes, how do I use the balancing/equilizing port on the bottom of the pack?
The actual procedure for balancing will be covered in the balancer's instructions.
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Old 01-13-2006, 11:11 AM   #96
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Thank you for answering my question.
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Old 01-13-2006, 02:33 PM   #97
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A little bit about me: I have been out of racing R/C for about 10-12 years or so, and started thinking about getting back into things now that my son is old enough, and to give me something to do when not racing the full scale race car. I have been flying electric airplanes and Lithium has been a big boost to electric flight. That said it is very frighting to me to see this technology come to R/C cars, indoor cars at that. These batteries can explode with impressive results, I know of cars that have been burned up, houses that have been lost, planes lost after a crash and a short. Different speed controlers are used to prevent the batts from discharging too low.
Now that said I think it would be great for R/C cars to have the bennifits that electric flying has been lucky enough to enjoy the past couple of years, but these batts are not to be taken lightly. I stole some info from a lipo battery thread on an electric forum I visit, I think that some of that info should be posted here:
It is long and some of it has to deal with some low power batts that are not applicable to R/C cars but the info is still very good.

1. Charging/Saftey IMPORTANT!
Until you are willing to follow all saftey precautions, DO NOT use lithium batteries. If your a type of person that prefers to push the limits of products, or be haphazard about following saftey requirements. Lithium technology is not for you. Read on to find out why.

Lithium cells must be charged very differently than NiCad or NiMH. They require a special charger specifically designed to charge lithium cells. In general any charger that can charge lithium ion can charge lithium polymer, assuming that the cell count is correct. You must NEVER charge lithium cells with a NiCad or NiMH only battery charger. This is dangerous. Charging cells is the most hazardous part of using lithium batteries. EXTREME care must be taken when charging them. It is important to set your charger to the correct voltage or cell count. Failure to do this can cause the battery to spew violent flames. There have been many fires directly caused by lithium batteries. PLEASE BE RESPONSIBLE when charging lithium batteries.

Here are a few MANDATORY guidelines for charging/using LiPos (Lithium Polymer Batteries).


1. Use only a charger approved for lithium batteries. The charger may be designed for Li-Ion or Li-Poly. Both batteries are charged in exactly the same. Some older cell phone chargers may charge the batteries .1 volt to low (4.1 vs 4.2), but that will not harm the battery. However, inexpensive lithium chargers are widely available and the use of cellphone chargers is highly discouraged.
2. Make certain that the correct cell count is set on your charger. Watch the charger very closely for the first few minutes to ensure that the correct cell count continues to be displayed. If you don't know how to do that, get a charger that you do know how or don't charge the batteries.
3. Use the Taps. Before you charge a new Lithium pack, check the voltage of each cell individually. Then do this after every tenth cycle there after. This is absolutely critical in that an unbalanced pack can explode while charging even if the correct cell count is chosen. If the cells are not within 0.1 volts of each other then charge each cell individually to 4.2 volts so that they are all equal. If after every discharge the pack is unbalanced you have a faulty cell and that pack must be replaced.
Taps are provided on most new lithium packs. Taps give you the ability to check individual cell voltages and charge one cell at a time. Make sure and get the appropriate connector to go into your taps. Don't try to stick you volt meter probes in the taps to measure voltage. They could slip and short your cells. Don't try to charge more than one cell at a time from the taps. Unless you have an isolated ground charging system, you'll short your batteries out. Refer to your individual cell maker for tap pin-outs.
4. NEVER charge the batteries unattended. This is the number one reason for houses and cars being burned to a crisp by lithium fires.
5. Use a safe surface to charge your batteries on so that if they burst into flame no damage will occur. Vented fire safes, pyrex dishes with sand in the bottom, fireplaces, plant pots, are all good options.
6. DO NOT CHARGE AT MORE THAN 1C unless specifically authorized by the pack vendor. I have personally had a fire in my home because of violating this rule. Todays highest discharge batteries can supposedly be safely charged at greater than 1C, however so far in all cases doing so shortens the life of the pack. Better to buy 3 packs than to try to charge 1 pack 3 times quickly. This may change in the future but as of Winter 2005 1C is still the recommended charge rate.
7. DO NOT puncture the cell, ever. If a cell balloons quickly place it in a fire safe place, especially if you were charging it when it ballooned. After you have let the cell sit in the fire safe place for at least 2 hours. Discharge the cell/pack slowly. This can be done by wiring a flashlight bulb of appropriate voltage (higher is voltage is ok, lower voltage is no) up to your batteries connector type and attaching the bulb to the battery. Wait until the light is completely off, then throw the battery away.
8. If you crash with your lithium cells they may be damaged such that they are shorted inside. The cells may look just fine. If you crash in ANY way carefully remove the battery pack from the aircraft and watch it carefully for at least the next 20 min. Several fires have been caused by damaged cells being thrown in the car and then the cells catch fire later and destroys the car completely.
9. Charge your batteries in a open ventilated area. If a battery does rupture or explode hazardous fumes and material will spew from the battery.
10. Keep a bucket of sand nearby when you are flying or charging batteries. This is a cost effective way to extinguish fires. This is very cheap and absolutly necessary.
11. It can happen to you, do not think to yourself that “it won't happen to me” as soon as you do that it you'll be trying to rescue your kids from your burning house or car. I'm very serious about this.

Now that we have covered that important topic let's move on to lighter matters:

2. Lithium What?
Lithium Polymer batteries are used in many electronic devices. Cell Phone, Laptops, PDA's, Hearing Aids just to name a few. Most, if not all, lithium polymer batteries are not designed for RC use, we use them in different applications than they were designed for. They are similar to Lithium Ion batteries in that they each have a nominal voltage of 3.6 volts, but dissimilar in that they do not have a hard metal casing but rather a flexible material encloses the chemicals inside. The "normal" lithium polymer batteries are thin rectangle shapes with two tabs on the top one positive one negative. The reason we use Lithium cells is that they are significantly lighter than comparable NiCad or NiMH batteries, which makes our planes fly longer and better.

3. Voltage and Cell Count:
LiPolys act differently than NiCad or NiMH batteries do when charging and discharging. Lithium batteries are fully charged when each cell has a voltage of 4.2 volts. They are fully discharged when each cell has a voltage of 3.0 volts. It is important not to exceed both the high voltage of 4.2 volts and the low voltage of 3.0 volts. Exceeding these limits can harm the battery.
The way to ensure that you do not go below 3.0 volts while flying is to set the low voltage cutoff (LVC) of your electronic speed control (ESC). It important to use a programmable ESC since the correct voltage cutoff is critical to the life of your batteries. Use the ESC's programming mode to set the LVC to 3.0 volts per cell with a hard cutoff, or 3.3 volts per cell with a soft cutoff. If your ESC does not have hard or soft cutoff, use 3.0 volts per cell. You will know when flying that it is time to land when you experience a sudden drop in power caused by the LVC.
If your ESC has an automatic lithium mode. Use it, it will correctly sense the number of cells and set the auto cutoff appropriately.
If you have previously been flying with NiCad or NiMH batteries, switching over to lithium polymer will result in a different number of cells being used. If you had 6 to 7 round cells then 2 lithium polymer cells will correctly duplicate the voltage of those cells. If you had 10-11 cells then 3 lithium polymer cells would be right for you. There are a lot of 8 cell flyer's out there that are stuck between 2 and 3 cells. In my experience the best option is to determine how many watts you were using before and duplicate that with your LiPos, Motor, and Prop. For example. If you were running 8 cells (9.6volts) at 10 amps on a speed 400 airplane, then you have 9.6 x10, 96 watts. So if you went with 2 lithium polymer cells (7.2 volts nominal) then you'd need to change your prop such that you used 13 amps. If you went to 3 LiPoly's (10.8 volts nominal) then you'd need to reduce the amperage to 8.9 amps. These estimates are approximate, and some experimentation is required for best results but conserving Watts is a good way to start.

4.10C from 3S4P? Naming conventions explained.
How fast a battery can discharge is it's maximum current capacity. Current is generally rated in C's for the battery. C is how long it takes to discharge the battery in fractions of an hour. For instance 1 C discharges the battery in 1/1 hours or 1 hour. 2 C discharges the battery in ½ or half an hour. All RC batteries are rated in milli Amp hours. If a battery is rated at 2000 mAh and you discharge it at 2000mA (or 2 amps, 1 amp = 1000mA) it will be completely discharged in one hour. The C rating of the battery is thus based on its capacity. A 2000mAh cell discharged a 2 amps is being discharged at 1C (2000mA x 1), a 2000mAh cell discharged at 6 amps is being discharged at 3C( 2000mA x 3).
All batteries have limitations on how fast they can discharge. Because of this many LiPoly batteries are put in parallel to increase the current capacity of the battery pack. When 2 batteries are wired positive to positive and negative to negative they become like one battery with double the capacity. If you have 2 2000mAh cells and you wire them in parallel then the result is the same as 1 4000mAh cell. This 4000mAh cell has the same C rating as the original 2000mAh cells did. Thus if the 2000mAh cells could discharge at a maximum of 5C, or 10 amps then the new 4000mAh cell can also discharge at 5C or (4000mA x 5) 20 amps. This method of battery pack building allows us to use LiPoly batteries at higher currents than single cells could produce.
The naming convention that allows you to decipher how many cells are in parallel and how many are in series is the XSXP method. The number in front of the S represents the number of series cells in the pack so 3S means it's a 3 cell pack. The number in front of P means the number of cells in parallel. So a 3S4P pack of 2100mAh cells has a total of 12 cells inside. It will have the voltage of any other 3S pack since the number of cells in series determines the voltage. It will have the current handling of 4 times the maximum C rating of the 12 individual cells. So say our 3S4P pack had a maximum discharge of 6C. That means that it has a nominal voltage of 10.8 volts (3x3.6) and a maximum discharge rate of 50.4 amps (2100mAh x 6Cx4P ).

5. Which battery should you buy?
With so many choices out there it is difficult to decipher what is marketing hype, what is brand
loyalty, and what is outright lies. Battery manufacturers are constantly trying to one up one another. While capitalism can drive prices down, it also can give cause to false claims about products.
One great way to find out what the best battery is, is to look at graphs of the batteries performance. Looking at how low the voltage of the cell drops at various amperages will give you a metric to compare that battery to similar size/weight batteries.
If graphs aren't your thing then simply look at what other people are using in successful setups that are similar to your application. If a lot of people are reporting long flight times and lots of power from airplane X, with power system Y, and battery Z and you do the same, then if your setup is similar the same battery will probably work well for you.
It pays to learn something about Watts, Volts, and Amps. Understanding these concepts is beyond the scope of this document, but can serve you well in not only figuring out what battery is best but also in your electric aircraft hobby.
I'm not convinced that a 30C battery is really any better than a 10 or 20C battery. Sure a higher C rating means it can discharge faster. But at the same time a battery discharged at 20C continuously will be empty in 3 minutes. Do you really only want to use the battery for 3 minutes? I love having burst power in helicopters and boats, but in almost all other applications actually running a battery at or above 20C is useless to me. I prefer to run batteries at 8-10 C and have a little headroom if I need it.
A final note on choosing a battery. Don't cheap out. Confirm that your batteries are capable of running that the amperage level you plan to use them at. Running a cell at a higher C rating than the battery can handle can not only damage your batteries, but it can also damage your speed control. Castle Creations has an excellent article on how using a weak battery can destroy a perfectly good speed control of any brand. Better to buy a bit better battery than you need than to destroy your electronics.

6. Dealing with temperature.
Lithium batteries like heat, but not too much. In the winter time, try to keep your batteries from the cold as much as possible. Leave them in the car while your flying, or keep them in your cargo pants... etc. At the same time don't let them heat up too much. Try to keep your batteries from reaching 160F after use. This will prolong the life of the cells. A good way to measure temperature is a handheld IR meter, they can be found for around $50.00 at most hobby shops.

If you have any suggestions for future sections or additions to the current document let me know and I'll add the information requested...if I know the answer!
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Old 01-13-2006, 03:11 PM   #98
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Stormer is very serious with the Platinum !
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Old 01-16-2006, 08:13 AM   #99
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Stormer is very serious with the Platinum !
It seems so. At the price they are offering the Platinum, it is a serious alternative to consider when buying new packs.
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Old 01-16-2006, 08:50 AM   #100
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Rick,

What's the difference between the Orion Platinum and the Peak Lipo? Tower has them both, but the Peak is about $25 more
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Old 01-16-2006, 09:06 AM   #101
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Originally Posted by CCristo
Rick,

What's the difference between the Orion Platinum and the Peak Lipo? Tower has them both, but the Peak is about $25 more
There is no difference between the two. I am not sure why there is a price difference but I will investigate.
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Old 01-16-2006, 09:48 AM   #102
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Tower prices are always higher on brand new/not-yet-released items, so they'll probably lower it soon.
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Old 01-16-2006, 09:55 AM   #103
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Rick-Have you guys tried putting one of these platimum LiPos in a Losi JRXS. I have a report from a fellow that could not get it in his car. It did not reach the point of touching the foam pads.
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Old 01-16-2006, 09:56 AM   #104
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Tower prices are always higher on brand new/not-yet-released items, so they'll probably lower it soon.
Yes that seems to be normal for them. But a big difference in price between the two is odd.
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Old 01-16-2006, 09:58 AM   #105
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Rick-question above your last post. We posted together.
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