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Pixel 9a Battery Health Assistance

From Consumer_Action_Taskforce

The Google Pixel 9a is an Android smartphone designed, developed and marketed by Google. The planned release date is April 10 in US, Canada and UK[1]. On March 31, 2025, Google announced its Battery Health Assistance[2] to users:

For Pixel 9a:

Lithium-ion batteries are consumable components that eventually require replacement. Your Pixel 9a will receive a software update that automatically helps manage the long term health and performance of its battery as it ages. This software will adjust the battery’s maximum voltage in stages that start at 200 charge cycles and continue gradually until 1000 charge cycles to help stabilize battery performance and aging.

You may notice small decreases in your battery’s runtime as your battery ages. Battery health assistance will also tune the phone’s charging speed based on adjusted capacity. You may notice a slight change in battery charging performance. Battery health assistance settings on Pixel 9a aren’t customizable by the user.

Background[edit | edit source]

Pixel 4a Battery Performance Program[3][edit | edit source]

Main article: Pixel 4a Battery Performance Program

Google is known for reducing the charging voltage of Pixel 4a from 4.4V to 3.95V via a software update, resulting in a 44% drop in theoretical usable charge[4]. Pixel 4a users report much higher real-world runtime loss.

Potential effects of software update[edit | edit source]

Google has not provided detailed technical explanations for the update, the adjusted battery's maximum voltage and charging speed are yet to known.

Battery Performance issues[edit | edit source]

Charging the battery at a lower voltage will not fully charge it. A partly charged battery exhibit shorter runtime. Lowering the charging voltage by 0.1V lowers the capacity by about 10%[5]. Charging the battery at a lower current will increase the charging time.

Google claimed that on Pixel 8a and later, the battery "should retain up to 80% capacity for about 1000 charge cycles"[2]. However, Google also said that "your battery’s actual lifespan depends on usage patterns and other factors"[2]. The "Battery Health Assistance", being a "factor", potentially causing battery lifespan to be considerably worse than advertised after the first thousand charging cycles.

Analysis[edit | edit source]

  • Charging the battery in shorter capacity periods leads to less runtime[4][5].
  • Charging the battery at lower percentages slows down battery aging[6].

Both factors lead to two possible outcomes that need to be differentiated very clearly to prevent misunderstanding, improve battery usage and identify anti-consumer practices:

  • When the user recharges the battery to a lower percentage frequently (only charging to 100% when necessary), the battery is aged less, which ultimately result in better battery health and longer runtime should the user need 100% capacity, compared to always fully charging.
  • The manufacturer blocked part of the available capacity after a certain amount of charging cycles. Meaning that after the user has degraded a certain amount of the battery, the manufacturer artificially limits its capabilities by further removing a second portion of the battery. Leaving the remaining amount available to degrade faster than normal.

Possible technical rationale[edit | edit source]

Prolonging battery life claim[edit | edit source]

Charging the battery at a lower percentage slows down battery degradation[6], However, there are some key differences between "Charging Optimization" and the future "Battery Health Assistance":

Charging Optimization has two options, Adaptive Charging and Limit to 80%[7]. Adaptive Charging can prolong the life of the battery by fully charging it just before the user unplugs, reducing the time spend at high charge levels. The user can select Limit to 80% option to help extend the lifespan of the battery with a drawback of a reduced runtime. The smart phone can always resume maximum available capacity should the user deselect the limit and charge it to 100%. Pixel users can enable and disable the feature at will.

Battery Health Assistance lowers the battery's maximum voltage and charging current in stages, from 200 cycles to 1000 cycles[2]. This is irreversible as the only way to use the full voltage of the battery again is to replace the battery itself[1]. This reduces runtime further as only part of the remaining battery capacity is available, defeating the purpose of preserving battery health.

Google claimed that this Battery Health Assistance will be voluntary for previously launched devices[8]. It is unclear whether some or all Pixel devices released in the future will be impacted by this program.

Safety consideration[edit | edit source]

Concerns arise over the delayed launch date of Pixel 9a over an "an unnamed component issue", suspecting that the issue could be the battery[9]. If the battery of the Pixel 9a is found to be defective, it might no longer be safe to charge at full voltage after 200 cycles.

Consumer reaction[edit | edit source]

Current and former Pixel users condemn this program and compared it with Apple's "batterygate" and the Pixel 4a Battery Performance Program, saying that Battery Health Assistance is "worse"[10] and the Pixel 4a incident is a "preview"[11].

Users also find the wording of the support article on Google's website vague and lack of self-consistency[12], saying the Google will "cause the thing they are supposedly trying to prevent"[13].

References[edit | edit source]

  1. ↑ Jump up to: 1.0 1.1 Brecher, Hannes; Fisher, Jacob (2 Apr 2025). "Google Pixel 9a comes with new feature that weakens the battery after just 200 charging cycles". Notebookcheck. Retrieved 2 Apr 2025.{{cite web}}: CS1 maint: url-status (link)
  2. ↑ Jump up to: 2.0 2.1 2.2 2.3 "Understand your Pixel battery". Google. 1 Apr 2025. Archived from the original on 4 Apr 2025. Retrieved 4 Apr 2025.
  3. ↑ "Pixel 4a Battery Performance Program". Google. 6 Jan 2025. Archived from the original on 7 Jan 2025. Retrieved 25 Mar 2025.
  4. ↑ Jump up to: 4.0 4.1 Wojciechowska, Kamila (5 Feb 2025). "There is even more to the Google Pixel 4a's horrific battery update than we thought". AndroidAuthority. Retrieved 4 Apr 2025.{{cite web}}: CS1 maint: url-status (link)
  5. ↑ Jump up to: 5.0 5.1 "BU-409: Charging Lithium-ion". Battery University. 25 Oct 2021. Retrieved 4 Apr 2025.{{cite web}}: CS1 maint: url-status (link)
  6. ↑ Jump up to: 6.0 6.1 Xu, Bolun & Oudalov, Alexandre & Ulbig, Andreas & Andersson, Göran. (2016). Modeling of Lithium-Ion Battery Degradation for Cell Life Assessment. IEEE Transactions on Smart Grid. 99. 1-1. 10.1109/TSG.2016.2578950.
  7. ↑ "Get the most life from your Pixel phone battery". Pixel Phone Help. Retrieved 4 Apr 2025.{{cite web}}: CS1 maint: url-status (link)
  8. ↑ Li, Abner (31 Mar 2025). "Google Pixel adding 'Battery health assistance' for long-term use, starting with Pixel 9a". 9to5Google. Retrieved 4 Apr 2025.{{cite web}}: CS1 maint: url-status (link)
  9. ↑ Mundy, Jon (20 Mar 2025). "Pixel 9a flaw uncovered before it even hits shops". Tech Advisor. Retrieved 4 Apr 2025.{{cite web}}: CS1 maint: url-status (link)
  10. ↑ "This is worse than Apple". Reddit. Archived from the original on 5 Apr 2025. Retrieved 5 Apr 2025.
  11. ↑ "Pixel 9a will have battery "optimised" after 200 cycles". Reddit. 2 Apr 2025. Retrieved 3 Apr 2025.{{cite web}}: CS1 maint: url-status (link)
  12. ↑ "So they want to reduce the wear out of the battery by... doing exactly the same? What's logic behind this?". Reddit. 1 Apr 2024. Retrieved 2 Apr 2025.{{cite web}}: CS1 maint: url-status (link)
  13. ↑ "Deliberate weakening after only 200 charging cycles: Google Pixel 9a limits battery voltage according to a planned schedule". NotebookCHECK - Notebook Forum. 2 Apr 2025. Retrieved 5 Apr 2025.{{cite web}}: CS1 maint: url-status (link)
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