Proper Storage Practices for Makita Batteries During Off-Season

1. Prepare Before Storage

Remove batteries from tools and chargers.
Clean metal contacts with isopropyl alcohol and a lint-free cloth; let dry completely.
Inspect visually for swelling, cracks, melted plastic, corrosion, or odd smells — retire any pack showing these signs. Do not store damaged packs.
Record model/serial and the date you put the pack into storage (apply a small label or sticker).

Pro tip: Photograph the pack label and housing condition; keep photos in your fleet log for warranty or return-to-service records.

2. Ideal State of Charge (SOC)

Target SOC for off-season: ≈ 30–50% (aim ∼40%).

Why: Storing at a moderate SOC reduces chemical stress (higher voltages accelerate calendar aging) and avoids deep-discharge risk if the pack self-discharges over months.

If a pack is fully charged, run a light tool task to bring it down to ~40%.
If a pack is deeply discharged, attempt safe recovery per Makita guidance or quarantine and recycle — do not leave packs at 0% for long.

3. Temperature & Humidity Conditions

Ideal storage temperature: 15–25 °C (59–77 °F).
Acceptable short-term range: 5–30 °C, but avoid freezing and prolonged exposure above 40 °C (104 °F).
Humidity: keep relative humidity <60%. Use silica gel in enclosed boxes if the area is damp.

Why: heat accelerates capacity fade and increases safety risk; freezing may harm BMS electronics or temporarily raise internal resistance.

4. Physical Storage Best Practices

Store packs upright with terminals protected (or as the pack design recommends). Avoid placing metal near the terminals.
Cover terminals or tape them lightly with non-conductive tape to prevent accidental shorts.
Store packs individually or separated by non-conductive dividers — do not pile loose packs together.
For fleets, use ventilated shelving or a fire-resistant cabinet for added protection.

Recommended supplies: labelled storage bins, individual plastic sleeves, silica gel packets, non-conductive dividers, and terminal covers.

5. Periodic Maintenance While Stored

Inspect every 3 months (monthly in hot/humid climates):
- Check SOC — top up to ~40% if it has fallen below ~30%.
- Visually inspect for swelling, corrosion, or any damage.
- Clean terminals if dusty or corroded.
For long storage (>9–12 months): perform a functional charge/discharge test every 6–12 months to confirm health.

Note: Top-ups are small—bring the pack to ~40% then return it to storage. Avoid repeatedly charging to 100% during storage maintenance.

6. Cold-Climate Specific Notes

Do not store packs in unheated garages where they may freeze — freezing risks BMS and cell damage.
If packs get cold during transit, warm to ≥5 °C (41 °F) indoors before charging or heavy use.
Use insulated pouches during transport in cold weather to limit thermal cycling and wind chill.

7. Transport & Shipping Considerations

Tape terminals and place each pack in a separate non-conductive bag/box.
Follow local and carrier regulations for shipping Li-ion batteries (commercial shipments commonly require UN38.3 compliance and carrier declarations).
For damaged or recalled packs, contact the manufacturer or a certified recycler before transport.

8. Recommissioning After Storage (Safe Return to Service)

Inspect visually and clean terminals.
Top up charge to working SOC (typically charge to 80–100% only if you need immediate full capacity).
Avoid heavy loads immediately after charging; let the pack rest 10–15 minutes before first use.
Run a gentle conditioning task (low load) the first time to confirm normal behavior (no odd heat, LED errors, rapid voltage sag).
If a pack shows unusual heat, poor runtime, error codes, or high voltage sag under light load — quarantine and test further; don’t return it to production.

Practice: monitor the first 2–3 uses after off-season before letting the pack go into full production.

9. When to Retire or Recycle Packs

Retire a pack if any of these are true:

Persistent swelling, leakage, or burning smell.
Capacity below ~60% of rated after proper testing.
Repeated BMS errors or persistent overheating during charge/use.

Tape terminals, label “DEFECTIVE — DO NOT USE” with date and observed symptoms, and take retired packs to a certified recycling / drop-off program — do not throw lithium packs in regular trash.

10. Fleet Management Practices (for multiple packs)

Label each pack: date stored, SOC at storage, inspector initials.
Rotate packs using FIFO (first in, first out) so oldest packs return to service first.
Keep a simple inspection log (date, inspector, SOC, notes) to spot recurring problems.
Consider keeping a small spare inventory for season start to avoid downtime if several packs fail.
For large fleets, consider periodic professional reconditioning contracts for high-value high-Ah packs.

FAQ (short)

Q: Can I store Makita batteries in a garage?
A: Only if the garage stays within the acceptable temperature range (ideally 15–25 °C). Avoid unheated garages that may freeze.

Q: How often should I top up stored batteries?
A: Every ~3 months (monthly in extreme climates) to keep SOC near ~40%.

Q: Is it OK to store at 100%?
A: Not recommended — long-term storage at 100% accelerates aging. Aim for ~30–50%.

Conclusion

Off-season care is low effort but high impact. Storing Makita LXT/CXT packs at a partial SOC in a cool, dry place, performing quarterly checks, and following safe recommissioning steps will preserve capacity, reduce BMS lockouts, and keep your fleet ready when the season returns. Implement the simple checklist above and you’ll cut replacement costs and reduce surprises.

Mnemonic: “3-50-6”

3 (months) — inspect every 3 months (monthly in extremes)
50 (%) — store around ~50% SOC (30–50% acceptable)
6 (months) — long-term test interval every 6–12 months