Independently verified: HPB Solid-State Battery passes PV8450 abuse tests without fire

Dr. Sebastian Heinz, CEO of High Performance Battery, says: “More than 30 years of research by our founder Prof. Dr. Günther Hambitzer had a single goal: to solve the causes of battery ageing and battery failure at their chemical root – not through additional protective electronics, but through the electrolyte itself. That our cells neither rupture nor burn, even in the nail penetration test and under internal short circuit, is precisely what that work was aiming at. What matters to us is that this is not our own assessment, but that of an independent institute.”

Seven tests, one result

Testing was carried out to PV8450-2021, one of the most demanding automotive test specifications for lithium cells. It covers electrical, thermal and mechanical abuse scenarios that deliberately exceed intended operating conditions: internal and external short circuit at room temperature and at 60 °C, overcharge, forced discharge, thermal stability and nail penetration. Altitude simulation and forced discharge were additionally carried out according to UN 38.3.

The results were classified according to SAND2017-6925 “Hazard Severity Level (HSL)”, the scale on which PV8450-2021 is also based. It ranges from HL 0 (no effect) to HL 7 (energetic failure). HL 5 denotes rupture, HL 6 fire or flame. None of the HPB cells tested reached these levels. The highest level assigned was HL 4 – visible leaking or venting without loss of mechanical integrity – and it occurred only in the external short circuit test. In the altitude simulation the cell showed no effect at all (HL 0).

Test | Hazard Level (HL) | Result

Internal short circuit (RT / 60 °C) | 3 | no rupture, no fire, no explosion

External short circuit (RT / 60 °C) | 4 | no rupture, no fire, no explosion

Overcharge (RT / 60 °C) | <2* |  no rupture, no fire, no explosion

Forced discharge | <2* | no rupture, no fire, no explosion

Altitude simulation | 0 | no rupture, no fire, no explosion

Thermal stability | 3 | no rupture, no fire, no explosion

Nail penetration | 3 | no rupture, no fire, no explosion


_{* HL 0 is possible for this cell chemistry. The final categorisation would have to be evaluated using further tests, which were not part of this project.}

Why the cell chemistry makes the difference

The decisive difference lies in the electrolyte. Conventional lithium-ion cells use a liquid, organic and therefore flammable electrolyte – it is the fuel that turns a thermal runaway into a fire in the first place. The solid electrolyte developed by HPB is non-flammable. It is not inserted as a prefabricated film but forms inside the already assembled cell. This removes the very mechanism on which the typical safety risks of lithium cells are based.

The same material property gives rise to the other characteristics of the technology: a cycle life many times higher than that of conventional cells, and a significantly improved environmental footprint over the service life. With HPB technology, safety, longevity and sustainability are not separately optimised objectives but consequences of the same chemical decision.

Heinz adds: “For licensees, investors and operators of stationary storage, safety is not a marketing question. It is a precondition for permitting, insurance and site selection. With the results from Ulm we now have a robust, externally generated basis for that. It is an important step on the way from technology to industrial application.”

From technology to industrial application

HPB develops and licenses battery technology rather than manufacturing in series itself. The technology is patent-pending in 96 countries and is granted through market, production and component licences. The focus is on stationary storage applications – wind and solar farms, industrial buffer storage and the production of green hydrogen – where service life and safety translate directly into economic viability. The results obtained to PV8450 form the safety basis for discussions with licensing partners.

Facts & figures on the abuse tests

Test specification:
PV8450-2021; altitude simulation and forced discharge according to UN 38.3

Testing institute:
Center for Solar Energy and Hydrogen Research Baden-Württemberg (ZSW), battery test centre Ulm

Scope:
7 test types – electrical, thermal and mechanical

Classification:
SAND2017-6925 “Hazard Severity Level (HSL)”, scale HL 0 to HL 7

Result:
no rupture, no fire, no explosion in any test

Highest HL value:
HL 4 (external short circuit) – below rupture (HL 5), fire (HL 6) and energetic failure (HL 7)

Test object:
HPB Solid-State Battery, sample cells

 

About HPB:
HPB develops a solid-state battery based on a non-flammable solid electrolyte that forms inside the already assembled cell. It builds on more than 30 years of fundamental research into the chemical causes of battery ageing. The company does not manufacture itself but grants market, production and component licences; the technology is patent-pending in 96 countries. The operating company, High Performance Battery Technology GmbH, is based in Bonn, Germany; High Performance Battery Holding AG is headquartered in Teufen, Switzerland.

 

About ZSW:
The Center for Solar Energy and Hydrogen Research Baden-Württemberg (ZSW) is one of the leading institutes for applied research into photovoltaics, renewable fuels, battery technology, fuel cells and energy system analysis. At its Ulm site, ZSW operates a battery test centre where electrical tests as well as mechanical, thermal and electrical safety tests are carried out in purpose-built test bunkers.