What’s the best way to store a battery from MacBook Pro (2014, retina) long-term? I want to swap it for a new battery, but this one is usable more or so. I want to store it for years, give me advice on what to do.

Storing a lithium-ion battery, like the one in your 2014 MacBook Pro Retina, requires careful handling to maintain its health over years. Here’s a comprehensive guide:

1. Charge Level for Storage

  • Ideal State of Charge: Store the battery at around 40% to 60% charge.
    • Fully charged or fully discharged states can degrade the battery over time.
  • To check the charge, reconnect the battery and verify its level periodically.

2. Environment for Storage

  • Temperature: Store the battery in a cool, dry place with a stable temperature.
    • Ideal temperature: 15–25°C (59–77°F).
    • Avoid freezing temperatures or excessive heat (>30°C or 86°F).
  • Humidity: Keep the humidity level low to avoid condensation or corrosion.

3. Container

  • Place the battery in an anti-static bag or a sealed, moisture-resistant container.
  • For added protection, include silica gel packets to absorb moisture.

4. Periodic Maintenance

  • Every 6–12 months, check the battery:
    • Reconnect it to the laptop to verify charge levels.
    • Recharge back to 40–60% if it has dropped significantly.

5. Handling and Safety

  • No physical stress: Avoid bending, puncturing, or placing heavy items on the battery.
  • Fire precautions: Store the battery away from flammable materials.
  • Consider using a fireproof battery storage case for added safety.

6. Label and Documentation

  • Label the battery with the date of storage and its initial charge level.
  • Include notes on when to check or recharge it.

Optional Long-Term Considerations:

  • If you’re storing it for multiple years and need a very safe solution, consider consulting a professional battery storage service or recycling center with experience in lithium-ion batteries.

By following these steps, you’ll maximize the chances of preserving the battery’s condition over the long term.

On Apple’s website, it’s stated that the battery is not lithium-ion, but lithium-polymer battery. Does it make any difference?

https://support.apple.com/en-us/111942

You’re correct that your 2014 MacBook Pro Retina utilizes a lithium-polymer (LiPo) battery. LiPo batteries are a subset of lithium-ion (Li-ion) batteries, distinguished primarily by their use of a polymer electrolyte instead of a liquid one. This design allows for flexible shapes and sizes, which is advantageous in compact devices like laptops.

In terms of long-term storage, the guidelines for LiPo and Li-ion batteries are quite similar. The advice previously provided—storing the battery at a 40–60% charge, in a cool, dry environment, and performing periodic maintenance—applies to both types.

One consideration specific to LiPo batteries is their sensitivity to physical stress. Due to their flexible casing, they can be more susceptible to damage from punctures or pressure. Therefore, it’s especially important to store them in a protective container and handle them with care to prevent any physical damage.

Additionally, while both LiPo and Li-ion batteries can degrade over time, some sources suggest that LiPo batteries may experience a slight hardening of the gel inside when left unused for extended periods, potentially affecting performance. Reddit Regular maintenance checks, as previously recommended, can help mitigate this issue.

In summary, while there are some nuanced differences between LiPo and Li-ion batteries, the general storage recommendations remain consistent. By following the outlined steps, you can help preserve your MacBook Pro’s battery over the long term.

Sources

Q: But if it’s depleted already, won’t it affect how often do I need to check the battery and recharge it slightly?

A: Yes, a depleted battery with significantly reduced capacity will indeed require more frequent checks during long-term storage. Here’s why and how to adjust your maintenance routine:

Why Depleted Batteries Require More Attention

  1. Faster Self-Discharge:

    • A degraded battery is more prone to self-discharge, meaning it will lose its stored charge faster than a healthy battery.
    • This can result in the battery dropping to critical levels (0% charge), which can cause permanent damage, especially in lithium-polymer batteries.

  2. Less Buffer Capacity:

    • With only 14.5% of the original design capacity remaining, even a small loss in charge can represent a significant percentage of the battery’s usable capacity.

Adjusting Your Maintenance Routine

  1. Check Charge Levels More Frequently:

    • Instead of the standard 6–12 months, inspect the battery every 3–4 months.
    • Reconnect it to the device and verify its charge level or use a multimeter if you’re storing it outside the laptop.

  2. Recharge When Necessary:

    • If the battery drops below 40% (367 mAh), recharge it to bring it back to 50% (around 460 mAh).
    • Avoid overcharging—only charge it up to 60% maximum.

  3. Be Mindful of Faster Degradation:

    • If the battery loses charge extremely quickly, consider that it might reach a point where it cannot hold any charge. In that case, long-term storage is no longer practical, and you may want to recycle it instead.

Pro Tip: Use a Smart Charger or Monitoring Device

Invest in a battery monitoring tool or charger capable of setting storage modes and thresholds. This can help automate the process and ensure precise charging without overshooting the desired levels.

In summary, a depleted battery requires closer attention to avoid falling to 0% charge, which can cause irreversible damage. Regularly checking and recharging every few months ensures the battery remains in a safe state during long-term storage.

So, do you mean here not the original capacity, which is 6330 [mAh], but current capacity, which is 918 [mAh]. What if I’d leave it with 80%?

Yes, when managing a heavily degraded battery, you should focus on the current capacity (918 mAh in your case), not the original capacity (6330 mAh). Here’s why and what happens if you store it at 80%:

Why Focus on Current Capacity?

  • The current capacity reflects the battery’s present condition and determines how much charge it can hold.
  • The original capacity is irrelevant for a battery with severe wear (like yours), as it can no longer hold that amount of energy.

Storing at 80% of Current Capacity

  1. 80% of Current Capacity (918 mAh):

    • 80% of 918 mAh = 734 mAh.
    • This would be considered a “high charge” state for the battery.

  2. Why High Charge Is Risky for Long-Term Storage:

    • Increased Oxidation: High charge levels accelerate chemical reactions inside the battery, leading to faster degradation over time.
    • Thermal Sensitivity: At higher charge levels, lithium-polymer batteries are more sensitive to temperature fluctuations, increasing the risk of swelling or failure if stored in less-than-ideal conditions.

  3. What Could Happen:

    • Over months or years, the battery may degrade even faster, reducing its already limited capacity.
    • If stored at 80% in a warm environment, there’s a higher risk of the battery failing prematurely.

Best Practice for Long-Term Storage

Even for a degraded battery:

  • Store it at 40–60% of current capacity (367–551 mAh for your case).
  • This range minimizes stress on the battery’s chemistry and reduces the risk of swelling or other damage.

If You Still Choose 80%:

  • Check and recharge the battery more frequently (every 1–2 months) since a high charge level may lead to faster self-discharge.
  • Ensure the storage environment is very cool and stable (15–25°C or 59–77°F) to mitigate degradation risks.

While 80% storage won’t cause immediate failure, it’s suboptimal for preserving a battery over the long term. For the best chance of maintaining its health, stick to 40–60%.