My batteries are boiling or smelling during charge!

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Product Series: All

Article No: FAQ035

Problem:  Excessive boiling, gassing, bubbling, or sulphur smell while charging flooded/wet batteries.

Possible Causes and Solutions: 

Note:  A certain amount of bubbling of the electrolyte is expected as water is electrolyzed.

1. Heat

Solution: Allow the batteries to cool after heavy use, or wait until ambient temperatures are lower before charging.  Lead-acid batteries should not be charged at temperatures above 50°C (122°F)!

2. Old/Poor condition batteries

Solution:  There is not much that can be done as batteries age and become more resisitive.  They will heat up more and consume more water.  Ensure frequent filling of water on older batteries.

NOTE:  Consult your battery manufacturer's manual for recommendations on water filling.

3. Inadvertent equalization

Dv/dt finish algorithms (#3, 7, 11, 71, 72, 73) run a minimum of one hour.  If the machine is just used for a few minutes then charged again, these algorithms will force extra overcharge into the batteries, causing additional boiling, but also serving to equalize the pack.

Solution: If this is not desired, run the machine until approximately 90% State of Charge before charging.

Ensure water is filled regularly if such a use case persists.

4. Incorrect charge profile

When using an algorithm meant for batteries with higher capacities, the cells will be exposed to higher currents than expected for extended periods of time.

Solution: The Original Equipment Manufacturer (OEM) for your machine or vehicle can provide you with the list of pre-loaded algorithms in your charger.

You can also visit our article containing all free to use algorithms files, algorithms description and instructions on how to upload them to your unit:

Download Algorithms for QuiQ Series Chargers

Download Algorithms for IC Series Chargers


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