ZenFone 8 Steady Charging not working as expected

atanasuzunovatanasuzunov Level 1
edited October 2021 in ZenFone 8

It looks there is no difference in charging speed with and without Steady Charging enabled. Charging from 20% up to 80%, in both cases takes ~30 minutes.

All system updates are installed.

That is an important functionality for increasing the battery lifespan.


  • sexiclube55sexiclube55 Level 2
    edited September 2021

    I use old chargers from previous phones 5V 1.5A(7.5W), 5V 0.85A(4.5W) and i think, this prolong battery lifespan ... This chargers are good for night charging(LOT of tíme) or i use slow chargers when im at work ... I use original fast charger only when im hurry... With 7.5W charger i need from 0 to 100% 3 hours. With 4.5W 5 hours .. this is really slow charging and saves battery... Also good option is 5V2A (10W)

  • Using a charger from an old phone is a good idea to workaround this issue. Still, it would be better if ASUS could fix that with a system update.

  • I think, is better to use old charger because working steady charging dont limit charging as slow charger

  • I noticed this behaviour and agree that it should be fixed, because even though re-using an old charger is good for the environment, we should be able to use the included charger with all advertised features.

  • I noticed that it depends on a charger you use. If you use original charger, you can limit it to min 15W (i think). With other 18W chargers, you can limit to 10W.

  • @atanasuzunov Last time I checked with a powermenter a couple of weeks ago, steady charging on Zenfone 8 worked as intended. (Voltage and current dropped according to spec.)

    While it won't give you any exact figures, SMMI test can at least show you if the values are lower when steady charging is enabled:

    • Open the calculator and input .12345+=
    • Single test -> AC charger test
    • Try it with and without steady charging enabled
  • There is really noticeable difference, at least between full 30W charing and 10W ultra stable. 10W charging works exactly like 5V 2A charger, so it's just working like it should.

  • gustav - can you please share differences between normal, steady and ultra steady charging ? (specs)

  • @sexiclube55 You can see for yourself:

    1. Connect AC charger
    2. Settings -> Battery -> Battery care -> Steady charging -> Charging rate limiter
    3. If you're using the stock 30W charger, these values should be 30W, 18W and 10W.
  • atanasuzunovatanasuzunov Level 1
    edited September 2021

    @Gustav_ASUS With ultra steady charging there is a noticeable difference. Charging is almost two times slower, which means ultra steady mode is working well. However, I'm wondering why I do not notice any significant difference between steady and normal modes. Does the normal mode works correctly then?

    The SMMI AC test for normal and steady charging shows voltage ~4.3V and a current flowing between 2 - 3.8A, mostly staying at ~3.8A, which means power ~15-18W. Since by specification, the charger can output from 5 to 20V, is it normal that voltage reported by the SMMI test does not raise above 5V?

    What are the standard values that should be observed in the SMMI test for the normal and steady modes?

  • This 4.3V IS battery voltage and not output charger voltage ... And small difference between normal and steady charging is because phone uses 30w charging only short time and then charging rate drops...

  • Thanks everyone for that clarification! I really wasn't aware that normal charging does not use 30w all the time. It looks most of the time it drops to 18w.

This discussion has been closed.