{"operation":"document","citation":"10-0264","title":"Liquid Robotics, Inc. — Hazardous Materials Safety Interpretation","source_type":"guidance","agency":"Pipeline and Hazardous Materials Safety Administration","status":"guidance","official":true,"published_on":"2011-02-18","effective_on":null,"summary":"10-0264 response to Liquid Robotics, Inc. concerning 173.185.","machine_formats":{"json":"https://regulus.evalyn.ai/document/phmsa-interpretation-10-0264.json","markdown":"https://regulus.evalyn.ai/document/phmsa-interpretation-10-0264.md"},"app_url":"https://regulus.evalyn.ai/document/phmsa-interpretation-10-0264","source_url":"https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretations/2010/100264.pdf","body":"<<<PAGE 1>>>\n\nU.S. Department of Transportation 1200 New Jersey Ave, SE\nWashington, D.C. 20590\nPipeline and Hazardous Materials\nSafety Administration\n/ FEB j 8 2011\nMr. Roger Hine\nPresident and CEO\nLiquid Robotics, Inc.\n1329 Moffett Park Drive\nSunnyvale, CA 94089\nRef. No.: 10-0264\nDear Mr. Hine:\nThis responds to your December 22, 2010 letter requesting clarification of the requirements in the\nHazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to lithium ion battery\npowered devices. Specifically, you ask us to confirm your understanding that the battery packs\ndescribed in your letter are considered separate lithium ion batteries and meet all ofthe applicable\nrequirements of § 172.1 02( c), Special Provision 188. In addition to your letter, you enclose a\ndrawing showing the configuration of the lithium ion battery packs.\nAccording to your letter, the device contains seven 95 Wh lithium ion batteries consisting oftwelve\n2.2 ampre hour cells in a 4S3P configuration. Your letter states that each of the lithium ion cells and\nthe battery pack both meet the applicable tests outlined in the UN Manual of Tests and Criteria. The\nseven lithium ion battery packs are mounted in an aluminum housing that is securely attached to a\ndrybox designed to both mechanically isolate and prevent any movement of the batteries during\ntransport or operation. Your letter further states that each of the battery packs are electrically isolated\nfrom each other through a set of solid state switches that can only be activated through the use ofan\nexternal plug inserted into its mating jack on the drybox. The drybox will be shipped without the\nplug inserted and the plug secured in a manner to prevent accidental activation. Additionally, a\ndistinct warning label affixed on the box instructs users not to transport the device with the plug\ninserted into the jack.\nBased on the information described in your letter, it is the opinion ofthis office that when the plug is\nremoved from the mating jack, the battery packs described in your letter are electrically isolated from\n\n<<<PAGE 2>>>\n\neach other and would constitute separate lithium ion battery packs. Further, the steps taken to\nprevent damage, short circuits and accidental activation during transport appear to meet the\nrequirements of § 172.102, Special Provision 188.\nI hope this answers your inquiry. If you need additional assistance, please contact the Standards and\nRulemaking Division.\nSiB~5~·\nBen Supko\nActing Chief, Standards Development Branch\nStandards and Rulemaking Division\n\n<<<PAGE 3>>>\n\n1329 Moffett Po.·k Drive\nSunnyvale, CA 94089\nPh# 650-493-6300 Fax: 408-747-1923\nwww.liguidr.com\nDecember 22,2010\nKevin Leary\nOffice of Hazardous Material Standards\nPipeline and Hazardous Materials Safety Administration\nU.S. Department ofTransportation\n1200 New Jersey Avenue. SE\nWashington, DC 20590\nRe: Wave Glider Lithium Ion Battery Design\nDear Mr. Leary:\nI am writing as a follow-up to our conference call on December 16, 2010 regarding the lithium\nion battery configuration that Liquid Robotics has designed to power our product known as the\nWave Glidel'TM. We would like confIrmation fmm PHMSA that our CUlTent understanding of the\nbattery configuration meets the requirements for the small battery exception in 49 CFR §\n171.102, Special Provision 188 of the U.S. Hazardous Materials Regulations (HMR) and thus is\nexempt from the requirements ofthe HMR. Our current understanding is based primarily on the\nbattery defInitions in the UN Manual ofTests and Criteria, the regulatory requirements for\nlithium ion batteries found at 49 CFR § 173.185 and the information in the following DOT\ninterpretation letters: Ref. #s 06-0015, 09-0066, 09-0182, 08-0029, and 10-0135.\nWave Glider\nThe Wave Glider is a madtime autonomolls surface vehicle that serves as a platform for\nscientific instrumentation as well as national security applications. The lithium ion batteries for\nthe Wave Glider are designed to power the navigation control system and are enclosed in a\nwatertight, hermetically sealed Delrin and aluminum drybox enclosure. Typical Wave Glider\ndeployments may operate thousands ofmiles from land and last up to a year. It will be important\nto ship these individual batteries contained within the drybox so end-users do not need to open\nthe drybox to install the batteries, and subsequently reseal the drybox. An impmperly performed\nresealing procedure would lead to failure of the navigation control system due to seawater\ndamage and potentially result in the loss ofthe system. The Wave Glider could be used in a\n\n<<<PAGE 4>>>\n\nvariety ofnational secudty and intelligence applications where resealing the drybox in the field\nafter shipment or losing the system would be unacceptable.\nLithium ion Batteries Designed for Wave Glider\nLiquid Robotics uses seven 95 Wh lithium ion batteries (manufactured by Inspired Energy model\n# NL2044) that consist of twelve 2.2 ampere-hour cells in a 4S3P configuration. Each\nceU has an equivalent lithium content O.66g, and each battery has an aggregate equivalent lithium\ncontent of7.92g. The lithium ion cells and batteries have been certified in accordance with the\nrequirements of the UN Manual ofTests and Criteria.\nThe batteries are installed in a rugged aluminum housing that is securely attached to the drybox\nto both mechanically isolate the batteries and to prevent any movement of the batteries in\nshipping or in operation. A diagram illustrating the Wave Glider battery system is enclosed with\nthis letter. The batteries are independently connected to the Wave Glider circuit board in order to\nprevent any individual battery from discharging and charging another individual battery. The\nbatteries are electrically isolated from the rest of the system through a set ofsolid-state switches.\nThe switches can only be activated when an external mechanical plug is inserted into its mating\njack on the drybox. The system is always shipped without the plug insel1ed into the jack (and\nhence deactivated) to prevent any accidental charge or discharge ofany individual battery that\ncould result in the creation of sparks or the generation of a dangerous evolution ofheat. Both the\nclear instructions in the Wave Glider user manual and a distinct warning label affixed on the\ndrybox by the jack instruct users to never ship the Wave Glider with the plug inserted into the\njack and the system activated. Furthelmore, during shipment, the plug is packed and secured in a\nmanner to prevent any possibility ofaccidental insertion into the jack and unintentional\nactivation ofthe system.\nIn addition, the \"Charge Control\" and \"Battery Power Combiner\" circuits (shown in the diagram)\nensure that each battery in the system is charged and discharged individually. To illustrate this\npoint, the system will charge and discharge the batteries safely and properly even if batteries of\ndifferent voltages, capacities, andlor chemistries are used in the same dl'ybox enclosure. There\nare no extemal connections to the battery circuits once the drybox is assembled to prevent any\npossibility ofextemaI shOl1ing. The drybox also is backfilled with dry nitrogen gas to further\nprevent any combustion within the drybox.\n* * *\nIn swnmary, we understand our battery design consists ofseven individual batteries that meet the\nrequirements of the small battery exception found in 49 CFR § 171. t02, Special Provision 188 of\nthe U.S. HMR, and, when these batteties are installed in the Wave Glider and offered for\ntransport, the Wave Glider also qualifies for the exceptions found in Special Provisio~ 188\n(provided the Wave Glider plug is not connected into the jack on the dry box containing the\nbatteries). We would appreciate written confilmation fi'om PHMSA that our understanding of\nthese lithium ion battery regulatory requirements is consistent with previous interpretation letters\nissued by PHMSA on this issue.\n2\n\n<<<PAGE 5>>>\n\nThank you very much for taking the time to discuss this matter with us on the phone and for\nresponding to our letter. Please feel free to contact our V.P. of Legal and Legislative Affairs,\nSuneil Thomas, at (415) 608-1608 or suneil.thomas@liguidr.comwith any questions.\nRoger Hine\nPresident and CEO\nLiquid Robotics, Inc.\n3\n\n<<<PAGE 6>>>\n\nWave Glider Battery System Diagram\nr Drybox enclosure\n/\n\"\nSolid State\nSwitches\nInspired Energy\nUN compliant 95W·hr Batteries\nI I\n1- 1-1 I\n1\nI\nI\nI\nInspired Energy\nUN compliant 9SW·hr Batteries\nI~.J\nI-I~\n•\n•\n•\nI\nI\n,\n•\n•\n•\n•\nInspired Energy\nUN compliant 9SW·hr Batteries\nI • J\nI-I-J\nI\nI\nI\nI\n\"Charge Circuit\nI-I-Control\nBreakers\n...\nCl1\nc: .:0\nCharge Circuit\nI----­\n0\nE i.-Control Breakers\nu\n.... Cl1\n~\n• 0\nc..\n>.\n• ....\n,$ •\n-\n•\nIX)\n• III\n•\nCharge\nCircuit\nI--­ I--Control Breakers\nSystem Control Electronics ../\n1-7 batteries may be\nplugged into the\nsystem\nI\nI\nI\nI\nI\nI\nPlug\nis inserted into\njack to activate Solid J:m:mo\nState Switches\nc=::>\nExternal\nPower Control ...\nJack\n- - - .I\n\"'I\nr~\nL..,..,..-~\n'-,..,..-'-'-,\nExternal\nConnectors\nExternal\nConnectors\nExternal\nConnectors","truncated":false,"body_characters":9048}