R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Electric Off-Road

Reply
 
Thread Tools Search this Thread
Old 01-16-2008, 08:16 AM   #1
Tech Master
 
*Chrominator*'s Avatar
 
Join Date: Feb 2006
Location: Living in a Van down by the river.
Posts: 1,146
Trader Rating: 19 (100%+)
Default Roar Approves Lipo

I found this in the Electric On-Road forum.

Yes, lithium battery technology is approved in ROAR sanctioned events.

The specs/rules will be in the 2008 rule book which should be available for download within a week (lots of reformatting to do) and the new approval forms for industry affiliates wishing for product approval will be online soon as well.

This is what will be formatted into the current rule book... difficult to follow if you are looking for rule numbers. But, has the information requested.

8.3 BATTERY RULES
8.3.1 Ni-Cd or NiMh Batteries
8.3.1.1 Shall be sub-C size rechargeable batteries rated at 1.2 volts or less.
8.3.1.2 Dimensions
8.3.1.3 (see 8.3.3 of 2007 rule book)
8.3.1.4 (see 8.3.4 of 2007 rule book)
8.3.1.5 (see 8.3.5 of 2007 rule book)
8.3.1.6 (see 8.3.6 of 2007 rule book)
8.3.1.7 (see 8.3.7 of 2007 rule book)
8.3.1.8 (see 8.3.8 of 2007 rule book)
8.3.1.9 (see 8.3.9 of 2007 rule book)
8.3.1.10 (see 8.3.10 of 2007 rule book)
8.3.1.11 (see 8.3.11 of 2007 rule book)
8.3.1.12 (see 8.3.12 of 2007 rule book)
8.3.1.13 (see 8.3.13 of 2007 rule book)
8.3.1.14 (see 8.3.14 of 2007 rule book)

8.3.2 Lithium Polymer Batteries (Li-Poly)
8.3.2.1 Lithium Polymer battery packs may be used to power electric racing cars if a Certification Of Compliance has been received and accepted by ROAR from the manufacturers of the battery packs. The Certification of Compliance indicates that the Lithium Polymer cells internal to the battery packs have been tested in accordance with UN T1-T8, the United Nations Recommendations on the Transport of Dangerous Goods, Manual of Test and Criteria (ST/SG/AC.10.11/Rev.4) and passed the acceptance criteria. Lithium Polymer battery packs that do not have UN certification must pass the ROAR testsROAR tests listed below and performed by the ROAR Li-Poly Test laboratory. Certification of Compliance to these test requirements and acceptance criteria shall be provided by the Original Manufacturer of the batteries. The Certification of Compliance will apply to all Lithium-Polymer products from the Original Manufacturer and provided on a one time basis. The Certification of Compliance can be sent directly to ROAR by the Original Manufacturer or supplied to ROAR by the Value Added Manufacturer that distributes the batteries. A Value Added Manufacturer must also provide ROAR a Statement of Origin identifying the Original Manufacturer of the cells used in the battery pack and the number of battery packs provided for sale within North America. The Value Added Manufacturer performs the assembly of cells into battery packs, installs the hard protective case and provides the electrical hook up points. The Original Manufacturer is the manufacturer of the individual cells.
8.3.2.2 Item Description
8.3.2.2.1 Li-Poly battery packs must have a hard, protective case that surrounds the cell(s) in the racing application. The maximum case size shall be as follows:
Length: 139mm +0mm/-3mm
Width: 47mm +0mm/-2mm
Height: 25.1mm +0mm/-3.0mm
The battery pack shall have leads extending from the case for the positive and negative electrical connections using wire of adequate size to handle discharge rates acceptable to racing applications. Alternatively, the case shall have external connection points for these wires clearly marked positive and negative so the user can apply the lead wires. Markings on the case are required stating the rated voltage and capacity of the battery. The Value Added Manufacturers name and/or logo shall be easily readable on the case. Individual cells used in the construction of the battery shall be rated at 3.7 VDC and the pack shall be 2 cells in series.
8.3.2.3 ROAR Impact/Drop Test
8.3.2.3.1 The cells of the battery pack shall experience no loss of mass, no leakage, no venting, no rapid disassembly, and no rise in temperature. The case shall not splinter or shatter in a manner that would create shrapnel and potentially puncture the cell inside.
8.3.2.3.2 The fully charged battery pack shall be dropped from a height of 5 feet to a flat concrete floor. The battery pack shall land flat on the floor during the drop.
8.3.2.4 ROAR Overcharge Test
8.3.2.4.1 The battery pack shall no display rapid disassembly resulting from Thermal Runaway.
8.3.2.4.2 The fully charged battery pack shall be charged to a value up to 12.0 VDC at a rate of 1 times the capacity of the cells in the battery pack for a period of 30 minutes (Example: 5000 mahr charge rate is 5 amps).
8.3.2.5 ROAR External Short Circuit Test
8.3.2.5.1 The battery pack shall not display rapid disassembly resulting from Thermal Runaway.
8.3.2.5.2 A 0.1 Ohm resistance shall be applied to a fully charged battery pack at room temperature (70 deg F +/-10). The test is concluded when the temperature of the battery pack returns to within10 deg of room temperature.
8.3.2.6 Li-Poly Battery Pack Approval
8.3.2.6.1 Li-Poly battery approvals will take place twice per year. Manufacturers applying for approval shall submit 4 battery packs to the ROAR Li-Poly baterybattery laboratory before April 1st or before October 1st of each calendar year. The results of each approval cycle will be announced either May 1st or November 1st of each calendar year on the approved battery list on the ROAR Website. Please find the battery approval form for Li-Poly batteries in the Approvals section of the ROAR website. Detailed instructions for submitting Li-Poly battery packs are provided on that form. A fee of $250.00 US is required to cover the testing costs by the laboratory.
8.3.2.7 General information about Li-Poly batteries.
8.3.2.7.1 Lithium Polymer packs must be charged with chargers capable of the industry standard CC/CV (Constant Current/Constant Voltage) charge profile.
8.3.2.7.2 Li-Poly batteries may be charged to a maximum of 8.40V +/-0.04V. Overcharging is a serious safety hazard and will not be tolerated.
8.3.2.7.3 All Lithium Polymer packs used for motor power must be charged inside a “Lipo Sack” or similar fire mitigation device proven to withstand a minimum of an 8.4v 5000mah Lithium Polymer pack failing destructively without showing external flame.
8.3.2.7.4 A Lipo battery pack is damaged when any of the following rules are broken. The damage is cumulative and cannot be reversed. These rules provide the safest operation and longest pack life. Going outside these rules may result in a destructive pack failure.
8.3.2.7.4.1 Do not over discharge Lithium Polymer battery packs and use a Proper ESC cutoff voltage. Some newer speed controls give you the option to set a cutoff voltage, and some do not. The cutoff voltage setting is working properly when the ESC does not allow the motor to spin anymore when the pack voltage reaches this set cutoff. A Lithium Polymer battery is damaged when it goes below a set voltage whether under load or not. The lower the voltage and the longer it stays low, the more damage is occurring to the cells. If your ESC doesn't have a setting for cutoff voltage, we strongly suggest not using any lipo pack with it unless you have a secondary device to cut off the motor at the correct voltage. By the time the pack “feels soft” at the end of the run or you notice any decrease in power, the pack has already been damaged. Consult your Lipo pack manufacturer for the proper low voltage cutoff since this value varies based on manufacturer.
8.3.2.7.4.2 The maximum safe temperature of a Lithium Polymer pack is 140degF. Generally the pack temp will INCREASE for about 5-10mins after the run is over, so measure the temperature of the pack immediately after the run and then again about 10 minutes later. The faster the car is geared, the more amps the motor is drawing and the battery is delivering. The less capable of outputting high current (amps) the pack is, the more it will heat up with the same load (think IB4200's vs. NiCad 2400's on a mod motor) Exceeding 140degF pack temperature causes damage, and the pack is also less efficient at near critical temperatures.
8.3.2.7.4.3 Only charge Lithium Polymer packs with a charger that uses the industry standard CC/CV charging algorithm for Lithium based batteries. There are two settings you will need to either set or verify on your charger each and every time before you begin charging a pack. The first is the pack voltage or cell count (each charger uses different nomenclature). If your charger is asking for the voltage of the pack, the choices are 3.7v (one cell), 7.4v (two cell), and 11.1v and beyond (3+cells). ROAR legal Lithium packs are all two cell, or 7.4v packs so set your charger accordingly. Some chargers ask for the cell count of the pack (one cell, two cells, and etc.) so you would set it for a two cell pack. The next setting is the charging rate. Lithium Polymer battery packs not only show no performance benefit from charging at higher than recommended rates, but they can be damaged by charging rates that are too high. The standard charging rate is “1C” which means the actual capacity of the pack in Milliamp hours. We charge in Amps not Milliamps, so divide the Milliamp Hours (Mah) of your pack by 1,000 to get your proper charging rate. For a 4800mah pack, 4800mah divided by 1,000 = 4.8 Amp charge rate. For a 3200Mah pack = 3.2 Amps, and a 5000Mah pack = 5.0 Amps. Unless specifically recommended by the manufacturer with no loss of cycle life, a maximum of 1C charge rate should always be used.
8.3.2.7.4 Lithium Polymer packs that will not be run for more than a month or two should be stored approximately half charged. Do not store them fully charged and do not store them near fully discharged (down to 6.0v) or damage will occur. The best way to know the charge state of a lipo is to use the Mah displayed on your charger when charging from fully discharged. For a 5000mah pack driven all the way to cutoff, charge it until you have 2500mah back into the pack and disconnect it from the charger for storage. Or use the discharge function on your charger, and discharge a fully charged pack to 1/2 of its capacity. So for a fully charged 5000mah pack, discharge 2500mah from it before long term storage.
8.3.2.7.5 There are six main root causecauses for lithium ion/polymer battery fires.
8.3.2.7.5.1 External Thermal Damage – Lithium Polymer cells will get damaged by external heat. Most manufacturers recommend keeping the cells under 60 deg C or 176 deg F. At about 90 deg C (194 deg F), the cell will start to balloon up as the electrolytes starts to break down and the internal layers start to delaminate. If the temperature is extremely severe (approx 190 deg C or 375 deg F) – the cell will go into thermal runaway and you will have a flaming mess. The thermal volatility is directly related to the cell chemistry used by the manufacturer.
8.3.2.7.5.2 Overcharge – Lithium Polymer cells are extremely non tolerant to an overcharge condition. A standard charge profile is CC/CV to 4.200V. Drastically overcharging a cell just once is a sure way to send a cell into thermal runaway. Overcharging a cell slightly but repeatedly is also extremely detrimental for a cell. For example, it you charge a cell to 4.300V, the lithium ions start plating on the electrodes forming lithium metal. Lithium ions are not flammable, but lithium metal is. Every slight overcharge cycle will plate more and more lithium metal resulting in a battery that is very prone to igniting. The best way to prevent overcharging is to charge through a balancer and to avoid chargers that do not charge with the standard 4.200V CC/CV charge profile.
8.3.2.7.5.3 OverdischargeOver discharge - overdischargingover discharging by itself is not dangerous, but it will destroy the cell. Overdischarging below the recommended cutoff voltage will cause the copper to start dissolving in the electrolyte. The dissolved copper will then start plating on the electrodes which may start an internal short circuit within the cell. The safety of the cell is compromised once the plating action starts and the next charge/discharge cycle will be of concern since there is now an internal short circuit. Don’t store you cells completely discharged. All cells have a small self discharge when left alone and if the self discharge takes the cell down below its minimum voltage, then the cell will be destroyed. It is recommended to disconnect the battery from all electronics (remove from speed controls, disconnect lithium polymer receiver packs from regulators etc) since most electronics have a small current drain even in the “off” position.
8.3.2.7.5.4 External Short Circuit – Lithium Polymer batteries have extreme current capability. When these cells are shorted out, the excessive current drain will cause the battery to overheat and possibly cause the cells to go into thermal runaway resulting in a possible fire.
8.3.2.7.5.5 Internal Short Circuit - this is mostly caused by contaminants getting into the cell at the cell manufacturing level. Contaminants can poke through the separator over time causing an interalinternal short where one of two things can happen. An internal short result in the cell having a high self discharge rate. Or an internal short can cause localizedcause localized heat buildup and initiate a thermal runaway condition – and thus another possible fire. Another source of internal shorts is the punching process the manufacturer uses to stamp out the anode and cathode electrodes. Some manufacturers use a low cost steel rule die and others manufacturers use a die that costs a couple orders of magnitude more. The lower cost steel die punchspunches tend to leave burrs on the electrodes, while the higher cost dies do not. Burrs have a tendency to puncture the separator and create micro-shorts. This micro-short will create an area of localized heat. In most cases, this will cause the cell to expand (puff up). In bad cases, this localized heat may be enough to ignite the cell. Every time you charge a cell, the cell will expand about 5% in the thickness dimension. This expansion/contraction may cause the burr to eventually rub through the separator. The vibrations and shock from RC use also causes the burr to rub against the separator. The infamous Sony recall was largely attributed to burr type contaminants.
8.3.2.7.5.6 External Mechanical Damage - A lithium polymer battery is made up of 20-30 layers of a very thin sheet copper anode, a thin plastic separator and a thin aluminum cathode. The vacuum sealed aluminum pouch keeps even pressure on the anode/cathode pairs. A dent can create a micro-short by making the stiff metal anode or cathode poke through the soft plastic separator. This microshort will create an area of localized heat. The cell will expand and then becomes a possible fire hazard. Another repercussion of a dent is that some layers of the cell will become delaminated and thus inactive. This means that the working layers will need to work harder to provide current and thus generate more heat in a localized area. ROAR believes that hard cases will greatly minimize the chance of external mechanical damage to the cells.
__________________
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Hi my name is Mike, and I'm a Chromeholic, my wheels have been chrome free for over a year, thanks to everyone who made fun of them.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*Chrominator* is offline   Reply With Quote
Old 01-16-2008, 09:17 AM   #2
Tech Legend
 
Cain's Avatar
 
Join Date: May 2002
Location: West Fargo, North Dakota
Posts: 29,548
Trader Rating: 240 (100%+)
Default

are there any limitations on voltage for the packs? (ie 7.4V, 11.1V) compared to NIMH?
__________________
Member - Red River Radio/Control Car Club
< Tekno EB48SL / SCT410.3 | Tekno EB410 x 2 | Yokomo YZ-2 DTM x 2 | LC Racing EMB-1 Buggies and Truggies >
Cain is offline   Reply With Quote
Old 01-16-2008, 09:34 AM   #3
Tech Addict
 
foolio's Avatar
 
Join Date: Jan 2006
Location: Indianapolis, IN
Posts: 732
Trader Rating: 3 (100%+)
Default

Quote:
Originally Posted by Cain View Post
are there any limitations on voltage for the packs? (ie 7.4V, 11.1V) compared to NIMH?
Is this what you mean:

8.3.2.7.2 Li-Poly batteries may be charged to a maximum of 8.40V +/-0.04V.

My question is does this apply to both stock and mod?
foolio is offline   Reply With Quote
Old 01-16-2008, 09:39 AM   #4
Tech Elite
 
Rick Hohwart's Avatar
 
Join Date: Sep 2003
Posts: 3,935
Default

Quote:
Originally Posted by Cain View Post
are there any limitations on voltage for the packs? (ie 7.4V, 11.1V) compared to NIMH?

The rules say 2-cell.
Rick Hohwart is offline   Reply With Quote
Old 01-16-2008, 09:47 AM   #5
Tech Master
 
jabroni racing's Avatar
 
Join Date: Mar 2005
Location: largo florida
Posts: 1,576
Trader Rating: 37 (100%+)
Send a message via Yahoo to jabroni racing
Default

Hmm, waiting to see if they do minimum weight revisions, since lipo's are quite a bit less..
__________________
www.facebook.com/jay3638
jabroni racing is offline   Reply With Quote
Old 01-16-2008, 09:59 AM   #6
Tech Elite
 
BSchorr's Avatar
R/C Tech Elite Subscriber
 
Join Date: Jun 2004
Location: Sioux Falls, SD
Posts: 4,820
Trader Rating: 92 (100%+)
Send a message via AIM to BSchorr Send a message via Yahoo to BSchorr Send a message via Skype™ to BSchorr
Default

Quote:
Originally Posted by jabroni racing View Post
Hmm, waiting to see if they do minimum weight revisions, since lipo's are quite a bit less..
No, the car still has to make weight, so you have to add weight to make weight!! lol

Great news! Now should I buy the Orion 3600 or the 4800!? 4800 would allow me to charge faster between heats if im tight for time.
__________________
Proline ~ Genesis R/C Products ~ First Premier Satellites
BSchorr is offline   Reply With Quote
Old 01-16-2008, 10:01 AM   #7
Tech Elite
 
Rick Hohwart's Avatar
 
Join Date: Sep 2003
Posts: 3,935
Default

Quote:
Originally Posted by jabroni racing View Post
Hmm, waiting to see if they do minimum weight revisions, since lipo's are quite a bit less..
No reason too change the weight limits.

Besides, when I run my T4 with a 5000 LiPo, it is still above the minimum legal weight.
Rick Hohwart is offline   Reply With Quote
Old 01-16-2008, 10:37 AM   #8
Tech Legend
 
Cain's Avatar
 
Join Date: May 2002
Location: West Fargo, North Dakota
Posts: 29,548
Trader Rating: 240 (100%+)
Default

Ah, missed it. was looking for voltage and not cell count.

So, whats the short list then on who is legal and who isn't?

Assuming the following for sure are legal:

Orion / Peak 4800
Orion / Peak 3200
Orion / Peak 3600
Trinity LiPro 4500

Anyone else a definite on the list?
__________________
Member - Red River Radio/Control Car Club
< Tekno EB48SL / SCT410.3 | Tekno EB410 x 2 | Yokomo YZ-2 DTM x 2 | LC Racing EMB-1 Buggies and Truggies >
Cain is offline   Reply With Quote
Old 01-16-2008, 11:01 AM   #9
Tech Elite
 
Join Date: Jun 2005
Posts: 2,570
Trader Rating: 26 (96%+)
Default

How about lithium ion cells? They are a perfect cell for saddle packs.
party_wagon is offline   Reply With Quote
Old 01-16-2008, 11:22 AM   #10
wyd
Tech Legend
 
wyd's Avatar
 
Join Date: Sep 2001
Location: Castle Mamba Max Pro. Feel its power!!!!!!!!!!
Posts: 21,142
Trader Rating: 50 (100%+)
Send a message via AIM to wyd
Default

Quote:
Originally Posted by Rick Hohwart View Post
No reason too change the weight limits.

Besides, when I run my T4 with a 5000 LiPo, it is still above the minimum legal weight.
I have the same thing with my buggy as I can pretty easily be over the weight limit with a lipo in.
__________________
Castle Creations (Since 2005) Just awesome products
Bumps & Jumps RC (Great Indoor facility for offroad and oval)
ST Racing Concepts (STRC)
Custom Works (Best Oval Cars around)
wyd is offline   Reply With Quote
Old 01-16-2008, 11:52 AM   #11
Tech Adept
 
Join Date: Sep 2006
Location: astoria, NY
Posts: 233
Trader Rating: 2 (100%+)
Default

Quote:
Originally Posted by Cain View Post
Ah, missed it. was looking for voltage and not cell count.

So, whats the short list then on who is legal and who isn't?

Assuming the following for sure are legal:

Orion / Peak 4800
Orion / Peak 3200
Orion / Peak 3600
Trinity LiPro 4500

Anyone else a definite on the list?
how are those trinity LiPro packs??? any good?? what cells are they?
__________________
DTX Evader ST Pro Brushless, Tx Mini E-Revo VXL
cheech4 is offline   Reply With Quote
Old 01-16-2008, 11:54 AM   #12
Tech Master
 
Orange's Avatar
R/C Tech Elite Subscriber
 
Join Date: Apr 2003
Location: Chandler, AZ
Posts: 1,277
Default

Reedy is going to have some soon. Its on the ASC website.

http://www.teamassociated.com/reedy/...eries_lipo.htm
Orange is offline   Reply With Quote
Old 01-16-2008, 01:39 PM   #13
Suspended
 
Join Date: Dec 2007
Location: Owensboro, Ky
Posts: 783
Talking Hello Cheech4 remember me from rcu!

Quote:
Originally Posted by cheech4 View Post
how are those trinity LiPro packs??? any good?? what cells are they?
Everybody seems to prefer the maxamps Lipo packs.
I personally like www.cheapbatterypacks.com batteries though.
__________________
MODIFIED 4-WHEEL*the class of champions*
River City RC Racers/Rectors Raceway/Hoosier Hobbies
Hpi Rs4 Mt converted to 2wd Brushless.
Associated B44/Tamiya 501x WE
Off-road only!
bmaglinger is offline   Reply With Quote
Old 01-16-2008, 05:56 PM   #14
Tech Champion
 
Jason Pelletier's Avatar
 
Join Date: Jul 2007
Location: New York
Posts: 8,820
Trader Rating: 33 (100%+)
Default

Quote:
Originally Posted by bmaglinger View Post
Everybody seems to prefer the maxamps Lipo packs.
I personally like www.cheapbatterypacks.com batteries though.
Those aint really roar legal though.......
__________________
Island Raceway & Hobby
Jason Pelletier is offline   Reply With Quote
Old 01-16-2008, 06:07 PM   #15
Tech Master
 
Crawler's Avatar
 
Join Date: Mar 2007
Location: I'm an A**HOLE!
Posts: 1,828
Trader Rating: 6 (100%+)
Default

Quote:
Originally Posted by RB FIVE View Post
Those aint really roar legal though.......
Max Amps have something in the works on this. It will be a detachable hard plastic cover that can be retrofited to current packs. In the next couple weeks they should have them in.
__________________
RCShortCourse.com

550 Mafia.
Crawler is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
ROAR approves LIPO and Brushless al dente Colorado Racing 12 01-23-2008 11:42 PM
ROAR Approves LIPO yyhayyim Electric On-Road 232 01-23-2008 05:44 PM
ROAR Approves Brushless Motors chicagokenji Wisconsin & Illinois Racing 5 07-17-2007 11:40 AM
ROAR approves Batteries.. Mason Electric On-Road 33 12-18-2005 08:29 PM
ROAR Approves batteries Mason Florida Racing 0 12-16-2005 01:49 PM



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 03:35 AM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net