How Different Battery Chemistries Handle Cold

Yes, chemistry matters. It means the materials inside the cells, and it's usually named on the label or in the manual. Cold hits every type. The rules for charging and for freezing differ, though, and that's where owners get caught out.

Every type loses some punch

Battery University says the momentary capacity decrease in the cold differs with battery chemistry.¹ The same page says that at -20°C (-4°F) most batteries are at about 50 percent performance level.¹

That's a broad rule of thumb for batteries in general. It isn't a figure for yours. Treat it as a reason to go and check what your own manual says about the cold.

Lead acid

Lead acid is the old car-battery type, and some older home battery banks still use it. Battery University says lead acid and NiCd have higher charging tolerances than newer systems such as lithium-ion.² It also says lead acid is tolerant, but lithium-ion needs special care.²

The weak point is freezing. The same page says freezing a lead acid battery leads to permanent damage.² It advises keeping the battery fully charged, because a discharged battery's electrolyte becomes more water-like and freezes earlier.²

Electrolyte is the liquid inside that carries the charge. Another page adds that with lead acid there's a danger of the electrolyte freezing, which can crack the enclosure.¹

Nickel-based

NiCd and NiMH are the nickel-based types. You'll mostly meet them in older cordless gear rather than home batteries. Still, the table is a handy contrast. It lists NiCd and NiMH charging from 0°C to 45°C, with a lower charge rate of 0.1C between -18°C and 0°C.²

The "C" figure is a charge rate. A smaller number means a gentler charge.²

Lead acid, nickel-based and lithium-ion are not interchangeable. A rule that suits one can harm another. Don't carry a cold-weather habit from your car battery over to a lithium pack.

Lithium-ion in general

Most modern home batteries and power stations are lithium-based. The reference's table lets lithium-ion charge between 0°C and 45°C, and permits no charge below freezing.²

Discharge is wider, at -20°C to 60°C in the same table.² That's why some units will run a load in the cold but refuse to charge. The full story is on the page about charging in the cold.

LFP

LFP is short for lithium iron phosphate. It's a type of lithium-ion battery with a different cathode material. Wikipedia says LFP generally has higher decomposition temperatures than some other lithium chemistries.³

That's a statement about heat stability. Cold is another matter. LFP isn't immune to it, and nothing in these sources says otherwise, so treat your own manual's cold limits as firm.

One maker's guide says even steadier LFP chemistry needs you to stay within the listed limits.⁴ LFP batteries, it adds, still need the right temperature, airflow and charge habits.⁴

Side by side

What to do

Look up which chemistry you own. Then read the charging range, not just the operating range. If your manual allows charging below freezing, follow its exact steps. A separate page on finding the limits in your manual shows how.