How Harsh is Cold Weather on Batteries?

[BGoat]

36 volt V-glide. Using Lester charger that came with cart. I have only done 2 quick voltage measurements, once just to verify the charger was working the first time I used it, 44. something volts if I recall correctly, then 47. something another time, again if I recall correctly.

[ThreeCW]

Originally Posted by Sergio

So at 20ºF, the normal 59.3v @ 77º F bulk charge for 24 cells should reach: 59.3 + (77-20) * 0.0028 * 24 = 63.13v

Sergio,

Great explanation why lead acid batteries are affected by cold temperature

My experience is the same as you explained in cold weather ... my static pack voltage is not affected by cold temperature (full charge remains at 51.7v), but the voltage drop when running the cart increases substantially as the temperature decreases, run time is reduced and the cart feels "sluggish".

Are any modern chargers temperature compensated to automatically adjust the charge voltage based on the ambient temperature?

Regards, 3CW

[Sergio]

It is about the battery (ideally internal) temperature, not the outside temperature.

Some charging systems do have temperature probes on the batteries to monitor the temperature and use the information to adjust their algorithym.

Typically the chargers algorithm will allow the voltage to rise depending on the feedback is getting from its calculations (dv/dt or otherwise), that is why You read the top voltage can vary from 60v to 64v.

The point was that the lower temperature reduces the chemical reaction rates inside the battery, both for charging and for discharging.

[ThreeCW]

Sergio - Makes sense ... thanks again