Tested properly,and we will show you.
Our sodium cells went through the UN 38.3 test series at an independent, ILAC-MRA accredited laboratory. The headline result is below, the documents are available on request, and nothing here is a claim we cannot put paperwork behind.
The result
70°C against a 170°C limit.
On the external short circuit test, our sodium cells peaked at 70°C. The limit is 170°C. That is not a marginal pass, and it is the number we would want to see if we were the ones buying.
The cells passed all applicable tests in the series. Testing was carried out by an independent laboratory accredited under the ILAC Mutual Recognition Arrangement — not in our own workshop, and not by us.
What the series covers
Eight tests, and none of them are gentle.
UN 38.3 is the standard test series cells are put through before they are considered fit to move. It exists because the failure modes it looks for are the ones that matter: heat, pressure, mechanical damage and electrical abuse. This is what the series consists of.
T.1 — Altitude simulation
Low pressure, simulating unpressurised air transport. Looks for leakage, venting and mass loss.
T.2 — Thermal cycling
Repeated swings between temperature extremes, to find seals and joints that only fail after they have been worked.
T.3 — Vibration
Sustained vibration across a frequency sweep — the closest thing in the series to life in a vehicle.
T.4 — Shock
Sharp mechanical shocks in every axis. Internal structure either holds or it does not.
T.5 — External short circuit
The terminals shorted deliberately, at temperature. This is the 70°C figure above, against a 170°C ceiling.
T.6 — Impact and crush
Deliberate mechanical damage to the cell, looking for fire and for case temperature afterwards.
T.7 — Overcharge
Charged well beyond its rated voltage on purpose, which is the abuse case we spend most of the Support page trying to help you avoid.
T.8 — Forced discharge
Driven below zero volts by the rest of a pack. The failure mode nobody thinks about until a bank is badly matched.
Cells are not packs
This testing was done on the cells. A finished pack is cells plus busbars, balancing and a case, and how it is charged and installed matters at least as much as what the cells can survive. The installation guide and the charging windows are the other half of the story, and they are the half you control.
Documents
Ask and we will send them.
We do not put these behind a form. If you need them, email us and say which pack and what you need them for — most requests come from dealers, insurers and people whose workplace wants paperwork before a battery comes through the door.
Safety Data Sheet
The SDS is the authority on handling, storage and what to do in an incident. If you have read something online about sodium chemistry and want it settled, this is the document that settles it.
Test report
The laboratory report for the cells used in our sodium packs. Available on request for the current line and the discontinued models.
Dealer paperwork
If you are stocking us, ask once and we will send the full set so you have it on file rather than chasing it per order.
In an emergency
What the guidance actually says.
DOT Emergency Response Guidebook, Guide 147
Guide 147 covers lithium ion and sodium ion together. For a small battery fire it calls for large amounts of water — not dry chemical, not CO₂. For anything larger, let it burn out and protect what is around it. Call 911 first and tell them it is a battery.
The water myth
You will read that water must never go near a sodium battery. That is true of sodium-metal and sodium-sulfur cells. It is not true of sodium-ion, which contains no metallic sodium. Full detail on the Support page.