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Tesla Powerwall sold on Lazada ????


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Hardly "Tesla" but it's in a nice box and the size and weight are about right for a 200Ah x 48V LiFePO4 pack, looks like a reasonably "smart" BMS too.

 

You could probably DIY a pack for half that but no nice pre-packaged box.

 

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19 minutes ago, BritManToo said:

70kbht seems expensive for 200AH.

200AH gel batteries cost 10Kbht but you can only use 1/2, so 200ah would in reality cost 20Kbht.

 

I'd rather pay 60Kbht for 600AH of usaable storage capacity in old tech.

 

Don't forget it's 200Ah @ 48V nominal (about 10kWh) ???? 

 

So you'd need 8 x the 200Ah gel batteries for the equivalent storage.

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16 minutes ago, BritManToo said:

Would it be a problem for the BMS inside if you put them in series , to create 48V ? I do know for parallel it is no problem ,

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7 hours ago, sezze said:

Would it be a problem for the BMS inside if you put them in series , to create 48V ? I do know for parallel it is no problem ,

 

It will work fine, mostly (and you could do it with 4 x 12V packs too which might be even cheaper).

 

A couple of caveats.

 

You need to top-balance both packs before connecting them in series so they both have the same charge level.

 

If you start out with one at low charge and the other at high charge then when in series the high charge one will become full and its BMS will cut off before the other pack has reached full charge (so it never will). Conversely when discharging the lower charge pack will become empty first and cut off the discharge path leaving unusable capacity in the higher charged pack.

 

Even with a top-balance any mismatch in capacity of the two packs will, over time, result in them getting further and further out of sync, eventually also leading to the above.

 

Of course, the issue is easily fixed by another top-balance.

 

Buy your packs from the same source at the same time to get the most similar packs.

 

I'll stick with my used golf-cart cells, 200Ah @ 1,600 Baht (about 80% of rated capacity left), 16 needed plus a 16s BMS.

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4 hours ago, Crossy said:

 

It will work fine, mostly (and you could do it with 4 x 12V packs too which might be even cheaper).

 

A couple of caveats.

 

You need to top-balance both packs before connecting them in series so they both have the same charge level.

 

If you start out with one at low charge and the other at high charge then when in series the high charge one will become full and its BMS will cut off before the other pack has reached full charge (so it never will). Conversely when discharging the lower charge pack will become empty first and cut off the discharge path leaving unusable capacity in the higher charged pack.

 

Even with a top-balance any mismatch in capacity of the two packs will, over time, result in them getting further and further out of sync, eventually also leading to the above.

 

Of course, the issue is easily fixed by another top-balance.

 

Buy your packs from the same source at the same time to get the most similar packs.

 

I'll stick with my used golf-cart cells, 200Ah @ 1,600 Baht (about 80% of rated capacity left), 16 needed plus a 16s BMS.

Here a Video about what Crossy is saying (it helped me to understand it better)

 

 

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