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Lithium batteries reactions A level chemistry

Hi, I have been studying the reactions that occur in a rechargeable Lithium battery. I am confused as to how the rechargeable aspect of it works. So I know that the oxidation reaction is Li reacts to give Li+ and e-, and the reduction reaction is Li+ + CoO2 + e- reacts to give Li+(CoO2)-, but when it is recharged, are both of these reactions reversed? surely this would change the sign of the EMF and it wouldn't be feasible? Many thanks
Original post by Bertybassett
Hi, I have been studying the reactions that occur in a rechargeable Lithium battery. I am confused as to how the rechargeable aspect of it works. So I know that the oxidation reaction is Li reacts to give Li+ and e-, and the reduction reaction is Li+ + CoO2 + e- reacts to give Li+(CoO2)-, but when it is recharged, are both of these reactions reversed? surely this would change the sign of the EMF and it wouldn't be feasible? Many thanks

You are providing electrical energy which drives the reaction in the opposite direction as the discharge reaction

That way the battery absorbs energy and is charged
Original post by BobbJo
You are providing electrical energy which drives the reaction in the opposite direction as the discharge reaction

That way the battery absorbs energy and is charged


Yes i understand that but what would the overall reactions be in the forward and backwards direction? Surely in the reverse direction they would have an EMF that is negative, hence not feasible?
Original post by Bertybassett
Yes i understand that but what would the overall reactions be in the forward and backwards direction? Surely in the reverse direction they would have an EMF that is negative, hence not feasible?

The overall reaction during charging is the reverse of that during discharging

You are providing an input of energy which drives the unfeasible reaction
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Pigster
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Original post by Bertybassett
hence not feasible?


The reaction is not feasible if left to its own devices. But you're not, you're shoving energy into the system and driving the process. Photosynthesis is not a feasible reaction at any temperature (DH = +ve and DS = -ve), but it stilled happens.
Original post by Pigster
The reaction is not feasible if left to its own devices. But you're not, you're shoving energy into the system and driving the process. Photosynthesis is not a feasible reaction at any temperature (DH = +ve and DS = -ve), but it stilled happens.

right, but what would the actual reactions be for the forward and reversible reactions?
Original post by Bertybassett
right, but what would the actual reactions be for the forward and reversible reactions?



if
A + B ⇌ C + D

The forward reaction is A reacting with B
The backward reaction is C reacting with D

The discharging reaction is the reverse of the charging reaction

The discharging reaction is the reverse of the charging reaction

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