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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: the_last_moose on February 14, 2021, 07:17:17 AM

Title: Chemical equation for the lithium iron phosphate battery
Post by: the_last_moose on February 14, 2021, 07:17:17 AM

The cathode of a lithium ion phosphate battery is made of LiFePO₄ and that upon discharging, it is transformed to FePO₄. The Anode is made of graphite.

The reactions for the discharge cycle are given as follows:
Cathode: LiFePO₄ ⟶ FePO₄ + Li⁺ + e^-
Anode: Li⁺ + C6 +e^- ⟶ LiC6

I find this answer difficult to grasp because this shows electrons being accepted in the anode. Anode should be oxidation hence it should show a loss of electrons. Can someone please clarify the reasoning behind these reactions?

Title: Re: Chemical equation for the lithium iron phosphate battery
Post by: chenbeier on February 14, 2021, 08:18:32 AM

It is a Battery not an electrolysis. At plus contact (Anode) electrons go in,
at cathode the negative contact they coming out.

Title: Re: Chemical equation for the lithium iron phosphate battery
Post by: AWK on February 14, 2021, 08:40:17 AM

The oxidation of Fe²⁺ to Fe³⁺ is rather related to battery charging.

Title: Re: Chemical equation for the lithium iron phosphate battery
Post by: chenbeier on February 14, 2021, 10:15:41 AM

Correct

https://www.researchgate.net/figure/Chemical-reaction-of-a-LiFePO4-cell-21_fig2_280886489