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Discussion Starter #1
Hello,

I am in the process of upgrading my 120v 225Ah lead acid pack to 144v 200Ah lithium and I am curious about the possibility of using my old, but still ok lead pack to store solar energy, from a bank of panels that I would need to purchase, and then feed that to my lithium pack. I am going to buy a new charger as well, and I see there are chargers that will take a lower voltage dc input and still satisfy the voltage needed to charge the lithium pack. Is this something that is practical, the price of panels has come down quite a bit lately and I am thinking this would be really great, are there any other things I will need to consider?

thanks
Brucifer
 

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Well; starting with: your FLA BATTERIES have lost some portion of their capacity which is not recoverable. If you can get by with that lessened capacity, then you should be ok. It won't charge an equal capacity Lipo pack fully. Maybe 2\3 full. Otoh, this is better than recycling them for scrap values.
 

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Discussion Starter #3
Well; starting with: your FLA BATTERIES have lost some portion of their capacity which is not recoverable. If you can get by with that lessened capacity, then you should be ok. It won't charge an equal capacity Lipo pack fully. Maybe 2\3 full. Otoh, this is better than recycling them for scrap values.
Ok thanks for your input piotrsko!
 

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I'd go with backup power for your house, possibly with a couple of dedicated circuits to keep the batteries exercised. Your FLA pack's rated value was 27 kW of storage when new, so it shouldn't be too much of a stretch to guess you could use perhaps 5 kWh daily and have backup power in emergencies. I'd use a quality grid tied inverter with battery backup function, and power the EV from the grid. This assumes you can tie onto the grid where you're at. Even though renewable energy seems to be everywhere, it's easy to forget that it really isn't as easy as it sounds.
 

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Discussion Starter #6
I'd go with backup power for your house, possibly with a couple of dedicated circuits to keep the batteries exercised. Your FLA pack's rated value was 27 kW of storage when new, so it shouldn't be too much of a stretch to guess you could use perhaps 5 kWh daily and have backup power in emergencies. I'd use a quality grid tied inverter with battery backup function, and power the EV from the grid. This assumes you can tie onto the grid where you're at. Even though renewable energy seems to be everywhere, it's easy to forget that it really isn't as easy as it sounds.
Hi Mark,
Indeed, it always seems like things arent as easy as they seem. :)
thanks
Bruce
 

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I'm using since 2 years a 12 kWh pack of used lead-acid batteries taken from 4 neighbor electric vehicles (Estrima Birò).
They work fine, although I was never able to charge them over 60%; I discharge them down to 40% before turning off my home lights... but actually it only happens between October and February (I have just 500 Wp panels installed, often shadowed by surrounding buildings).

My system is rated 24V, but if you can afford a 48V inverter, batteries will last even longer as they'll have to provide low current: with all my 12 fluorescent&led lamps on, I need no more than 300W current, which at 48V means 6A; when onboard the EVs these batteries had to tolerate 40-80A.

I spent 300.00 dollars for the pack (the previous owner was going to trash them).
 
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