ebikes-sf
100 mW
I've had very disappointing experience buying LiFePO4 battery packs labeled VPOWER from ebay sellers power_battery_a123 and volgood which actually seem to be the same guy. Here is list of sellers who sell same VPOWER product:
power_battery_a123
ep-battery
volgood
vpower.hk
CAMMY_CC
I purchased seven 48v 20Ah and one 48v 10Ah. 5 charges burned with in 15 minutes and remaining 3 within 2 charges.
I tested capacities using Cycle Analyst and all were below 50%. I measured cell group voltages and they rangedfrom 3.2 to 3.8 volts meaning packs were very unbalanced. Then I used single cell charger to even/balance cell group voltages to 3.6v - capacities went up to 75-80%. However, cells got unbalanced with each charge/discharge cycle eventually reducing capacities back to below 50%.
I've been communicating with sellers for over 1.5 months now and responces were from "I can't believe" and "it's impossible" to "what tools did you use to measure?" and "send me pictures" but I never got any help.
I chose surface shipping which took 2 months for delivery so I couldn't open PayPal claim since it must be opened within 45 days. Luckily I used credit card for PayPal funding source and was able to open dispute against sellers' paypal accounts and will likely get money back but it may take 2-3 months. My advise for anyone buying from China and choosing surface shipping - open PayPal claim right away and just close it when item is received.
I contacted few buyers who left positive feedback for those sellers and it seems most of them never measured actuall capacity, couple of guys measured it after we talked and got similar disappointing results.
IF YOU WENT THROUGH SAME EXPERINCE, PLEASE, PLEASE DON'T LEAVE IT UNNOTICED, AND FOLLOW STEPS BELOW!!! I talked to ebay security dpt and they said I should report the item even if it does no longer show in the queu of purchaced items. It helps them to track bad sellers. Here are the steps:
1. Since ebay transaction log lives only up to 60 days, go to you PayPal account history, locate the transaction, and extract ebay transaction ID from transaction details.
2. Login to ebay and click "Resolution Center" link at the bottom of home page.
3. Select "I received an item that does not match the seller's description" and continue.
4. Paste the item number in textbox but don't click "Find Item", just click "Continue". Done.
power_battery_a123
ep-battery
volgood
vpower.hk
CAMMY_CC
I purchased seven 48v 20Ah and one 48v 10Ah. 5 charges burned with in 15 minutes and remaining 3 within 2 charges.
I tested capacities using Cycle Analyst and all were below 50%. I measured cell group voltages and they rangedfrom 3.2 to 3.8 volts meaning packs were very unbalanced. Then I used single cell charger to even/balance cell group voltages to 3.6v - capacities went up to 75-80%. However, cells got unbalanced with each charge/discharge cycle eventually reducing capacities back to below 50%.
I've been communicating with sellers for over 1.5 months now and responces were from "I can't believe" and "it's impossible" to "what tools did you use to measure?" and "send me pictures" but I never got any help.
I chose surface shipping which took 2 months for delivery so I couldn't open PayPal claim since it must be opened within 45 days. Luckily I used credit card for PayPal funding source and was able to open dispute against sellers' paypal accounts and will likely get money back but it may take 2-3 months. My advise for anyone buying from China and choosing surface shipping - open PayPal claim right away and just close it when item is received.
I contacted few buyers who left positive feedback for those sellers and it seems most of them never measured actuall capacity, couple of guys measured it after we talked and got similar disappointing results.
IF YOU WENT THROUGH SAME EXPERINCE, PLEASE, PLEASE DON'T LEAVE IT UNNOTICED, AND FOLLOW STEPS BELOW!!! I talked to ebay security dpt and they said I should report the item even if it does no longer show in the queu of purchaced items. It helps them to track bad sellers. Here are the steps:
1. Since ebay transaction log lives only up to 60 days, go to you PayPal account history, locate the transaction, and extract ebay transaction ID from transaction details.
2. Login to ebay and click "Resolution Center" link at the bottom of home page.
3. Select "I received an item that does not match the seller's description" and continue.
4. Paste the item number in textbox but don't click "Find Item", just click "Continue". Done.