[sagyam]

First report for Donut lab battery is out. Here is the TLDR

Specs

    26 Ah nominal capacity at 1C discharge rate

    94 Wh nominal energy with 3.6V nominal voltage

    Operates within 2.7V – 4.15V recommended range (max charging to 4.3V)

What was verified

    5C charging (130A): 0-80% in ~9.5 minutes, 0-100% in ~13.5 minutes

    11C charging (286A): 0-80% in ~4.9 minutes, 0-100% in ~7.3 minutes

    Successfully delivered 98.4-99.6% of charged capacity even after extreme 11C charging

Thermal Management

    Tested with both one-sided and two-sided heat sinks to simulate real-world conditions

    With dual heat sinks: Peak temps of 47°C (5C) and 63°C (11C) — well within safe limits

    With single heat sink: Reached 61.5°C (5C) and up to 89°C (11C) — still functional but approaching thermal limit

Missing claims

    Energy density: No weight and volume was mentioned

    Cycle life: VTT ran only 7 test cycles total.

    Cost Claims: Nothing about cost is mentioned

    Material Claims: No chemical analysis or materials analysis.

    Extreme Temperature Performance: No cold weather testing. No high-temperature testing.

    No abuse testing: No nail penetration, no overcharge, no short-circuit, no crush tests.

But according to the company website another report will drop next monday (March 2nd).

[taneq]

It’s good to know that it does at least perform about as well as current conventional batteries. The energy density and cycle life were the really off-the-wall claims. It’s exciting to hear that they’re continuing to test, can’t wait for more third party results!

Edit: Reading the report, they talk about “charge capacity” (Amp hours in/out) efficiency of 98.4% to 99.6%, but this seems potentially misleading. The actual charge energy efficiency is more like 90%.

> Successfully delivered 98.4-99.6% of charged capacity even after extreme 11C charging

Note the Wh numbers for discharge vs. charge energy.

> Discharge capacity Charge capacity Discharge energy Charge energy

> Cycle 1 26.109 Ah 26.159 Ah 91.021 Wh 100.793 Wh

[cogman10]

Yup, those 2 are the ones I really want to see.

The energy density isn't out of line if this is a true solid state battery. The cycle life, though, is AFAIK. I don't believe solid states have that sort of cycle life.

[PoignardAzur]

> Energy density: No weight and volume was mentioned

Note that the report includes some photos of the battery, so we can assume that it's not, like, several orders of magnitude larger than what they advertised.

EDIT: Honestly, I'm pretty excited. Even if their promises on cost and materials don't pan out and the lifetime turns out to be terrible, what they've just demonstrated is already a game-changer.