BQ34Z100-G1: Learning Cycle Failure

Hi Damian,

Thanks for your response, i did read that design energy can only be between 1 and 10 however in contradiction section 7.3.12 says that "it is recommended to scale by a factor between 1 and 10 to optimise resolution" which suggests that it is possible to use higher values whilst sacrificing resolution. We used a factor of 13 because our cells are 110Ah at 3.7V nominal and we can only enter an accurate 'Design Energy' of 412Wh with a design energy scale of 13 or greater.

We have had many attempts at this learning cycle. At first we used a design energy scale of 10 however the learning cycle failed in the same way as above. We assumed this was because of an incorrect design energy.

The cycles we have performed are as follows:

• Charge at C/2 (55A) discharge at C/5 (22A) performing the full learning procedure i included in my last post, qmax never updated. We used a scale factor of 10 for this cycle. We suspected the reason for the failure was due to a high cell terminate voltage of 3.3V. On the subsequent learning attempt we lowered this to 3.2V, kept all other conditions the same but it failed in the same way.
• Looking at previous learning cycles we have performed on different cells in the past, we noticed that we'd used C/5 for both charge and discharge. This learning cycle was performed and the same behaviour was observed.
• The cycle that i described in my previous post with a design energy scale of 13

Is it the case that our cells have too much energy to be used with this particular device?

James