Battery Testing Calorimeter (BTC) Adiabatic “ARC” - Type System for Thermal Runaway and Other “Abuse” Tests on Batteries and Their Components

Battery Testing Calorimeter (BTC) Adiabatic “ARC” - type system for thermal runaway and other “abuse” tests on batteries and their components. The BTC determines safe working limits to avoid thermal runaway explosion under “worst case” (adiabatic) conditions – provides data that can be relied upon in real-life applications. The limits can only be measured with an adiabatic device, any other system will not provide safe values. The specific measurements are:  Maximum safe temperature  Maximum discharge rate (current)  Maximum charge (voltage)  Specific heat, gas sampling and photographic evidence  Nail penetration and short-simulation The last two measurements do not strictly need to be in an adiabatic device but the BTC provides a convenient and safe environment in which to do them. The discharge current and charge voltage tests require integration with a cycler, which can also be supplied.

HEL BTC-500 HEL BTC-130

Version Compact: BTC-130 Large Scale: BTC-500 Foot Print TO MEASURE TO MEASURE Internal Diameter 13cm (~5 inches) Internal diameter of 50cm (~20 inches) Internal Height Internal height of 20cm (~ 8 inches) 30cm (12 inches) or 50cm Battery Types Used for any battery type as well as electrolytes, All the samples listed for the BTC-130 can be tested anodes, cathodes, SEI etc. Cyclindrical 18650 here as well as larger EV, HEV, military and space air- and larger sizes, pouch, prismatic, button plus all craft samples. manner of samples can be tested. System works equally well for small batteries and components. Operator Steel enclosure built into compact “Phi-TEC” Stainless plate (20mm thick) is used for the end Safety frame, is suitable for standard fume hood. plates and steel plate is also used for the cylindrical Enclosure is vented to prevent any pressure sides. Mechanical relief as well as software and oper- build-up, plus automated shut down in case of ator triggered shut down provides layers of protection excessive high temperature. for any eventuality.

T: +44 (0)20 8736 0640 E: [email protected] W: www.helgroup.com W: www.hazards.co

Safety and Calorimetry Battery Testing Calorimeter

Application and Technical Features

 Thermal Runaway Limits The main function of the BTC is to create the “worst case” invironment (ie adiabation conditions) under which limits for thermal runaway explosion can be measured. These conditions are: maximum battery temperature, maximum safe discharge current and maximum overcharge (voltage). The safety parameters should only be determined adiabatically – data from other (e.g. standard laboratory or ovens) will not be suitable and does not conform to battery safety testing standards.

Diagram shows step-wise heating of battery until the maximum safe temperature (‘onset”) is reached, after which thermal runaway driven by heat from the battery takes over

 Battery Short Simulation Battery shorts are a huge concern as they can lead to thermal explosion at any time. The consequences of this can be simulated by artificially creating a short between the terminals, while the battery sample is inside the BTC. A range of resistances can be tested to allow for “soft” and “hard” shorts.

 Remote Video - Viewing Via Probe Video camera integrated into HEL software for real-time visualisation and also recording of selected sequences. Real-time video recording of events inside BTC.

 Specific Heat Determination Specific heat Capacity (Cp) can be determined for the battery or pack, totally automatically. This can for example be used in computer modelling.

 Nail Penetration Apparatus Mechanical rig to simulate “mechanical” abuse via nail penetration. Nail speed and penetration distance can also be specified through the software. Also a range of “nail” sizes can be used.

 Gas Sampling Gas generated in thermal runaway can be automatically sampled by opening a valve through the software. This feature can also be used to divert the gas to a GC.

 Extra Analogue Inputs Up to 4 Analogue inputs from any client supplied device can be recorded and displayed, together with all other calorimeter data.

 Extra Temperature Sensors 8 extra sensors (type-K thermocouples) can be supplied for measuring battery temperatures at different locations during self-heating. Working range -100 to 1000C, fully logged on software.

Hel.ltd @heluk Hel-ltd

T: +44 (0)20 8736 0640 E: [email protected] W: www.helgroup.com W: www.hazards.co