I have looked at these before and was put off by cost and fire risk but I have recently started looking at them again.
The advantages are;
They charge at a constant rate. When you charge a lead acid battery the bulk stage is fine but when it gets to the absorption stage your solar panels output current is not totally used and is therefore wasted. When you charge a lead acid battery it is at best 85% efficient a lithium battery is 99%. So you get more out of your solar panels.
A lead acid battery needs to be regularly fully charged to maintain its capacity. A lithium based battery can run between 50%-95% and anything in between without needing a full charge.
A lithium battery happily works on a depth of discharge down to 85% whereas a lead acid battery only gives 50%. So a 100AH lead acid is effectively only a 50AH battery a 100AH Lithium based battery is 85AH.
A lithium based battery is less than half the weight usually for it's rated capacity . So you can either have twice as many for the same weight or have less weight for the same capacity. Please see previous paragraph though.
A lithium battery doesn't suffer from Peukert’s losses. So if you pull a large current for an inverter you don't lose the capacity of the battery like you do with lead acid.
A lithium based battery appears to have a lifespan in excess of twice the number of cycles of a lead acid battery if not more.
Finally the fast charge rate. If you have charger capable you can fully charge a Lithium battery in half an hour and the charge rate doesn't slow down.
ok. The downsides are they cost a bleeding fortune which is where this post comes in.
I have been looking at a lot of youtube videos where people have been using 18650 batteries to make battery packs for their e-bikes. I am now looking into doing the same using batteries from recovered laptop batteries.
I am aware of the need for BMS and specialised charger etc etc.
I am just wondering if anyone else on here has done anything similar before. Also thought it might make an interesting thread for people who are interested in the techy stuff.
@Techno I don't know why you but your name popped to mind
The advantages are;
They charge at a constant rate. When you charge a lead acid battery the bulk stage is fine but when it gets to the absorption stage your solar panels output current is not totally used and is therefore wasted. When you charge a lead acid battery it is at best 85% efficient a lithium battery is 99%. So you get more out of your solar panels.
A lead acid battery needs to be regularly fully charged to maintain its capacity. A lithium based battery can run between 50%-95% and anything in between without needing a full charge.
A lithium battery happily works on a depth of discharge down to 85% whereas a lead acid battery only gives 50%. So a 100AH lead acid is effectively only a 50AH battery a 100AH Lithium based battery is 85AH.
A lithium based battery is less than half the weight usually for it's rated capacity . So you can either have twice as many for the same weight or have less weight for the same capacity. Please see previous paragraph though.
A lithium battery doesn't suffer from Peukert’s losses. So if you pull a large current for an inverter you don't lose the capacity of the battery like you do with lead acid.
A lithium based battery appears to have a lifespan in excess of twice the number of cycles of a lead acid battery if not more.
Finally the fast charge rate. If you have charger capable you can fully charge a Lithium battery in half an hour and the charge rate doesn't slow down.
ok. The downsides are they cost a bleeding fortune which is where this post comes in.
I have been looking at a lot of youtube videos where people have been using 18650 batteries to make battery packs for their e-bikes. I am now looking into doing the same using batteries from recovered laptop batteries.
I am aware of the need for BMS and specialised charger etc etc.
I am just wondering if anyone else on here has done anything similar before. Also thought it might make an interesting thread for people who are interested in the techy stuff.
@Techno I don't know why you but your name popped to mind
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