I ordered 16 280Ah Varicore cells for $2020 via AliExpress from the LiitokalaVariCoreFlagship Store. It took two months for the cells to be delivered from China to Arizona.
All 16 cells were capacity tested with an EBC-A40L tester upon receipt, and all cells tested to 85% of 280Ah advertised capacity. An average of 238Ah capacity was measured for all 16 cells.
Below is the capacity test result for cell 6 (238.1Ah measured capacity). The capacity test results for cells 5-12 are attached. The blue curve is voltage in volts, the red curve is amperage in amps, and the horizontal axis is time in hours. The capacity test results are in Ah and the energy units are Wh. The test charged the cell fully using 3.65V, followed by a 30 minute wait, followed by a discharge at 40A until 2.5V reached, then charged at the end in order not to leave the cell in a discharged state. The max charging and discharging rate for the EBC-A40L tester is 40 amps, corresponding to 0.143C for these cells.
The manufacturer specifications for these cells shows capacity degradation vs. cycle below. The horizontal axis is cycle number and the vertical axis is percent of 280Ah capacity. We see that 85% measured capacity corresponds to 2750 cycle loss. The lifetime cycles was advertised to be 4000 cycles for these cells.
Lifetime Ah is defined as the total Ah over all 4000 cycles. Percent Lifetime Ah loss of these cells = the area under the above curve out to 2750 cycles divided by the area under the curve out to 4000 cycles. Doing that calculus, Lifetime Ah loss = 73.4%. I disputed the transaction and requested a 73.4% refund based upon Lifetime Ah loss.
I paid for 8 of the cells with a credit card and 8 of the cells with Paypal. All were bought on the same day in May 2021. AliExpress dispute resolution was horrible. They resisted the 73.4% refund, sided with the seller fraud, and closed the dispute associated with each package of 4 cells. In response, I contacted my credit card company and Paypal. The credit card company, Chase, was excellent. My credit card now shows a full refund. Paypal dispute resolution has so far been horrible. Paypal completely ignored all the definitive evidence that I provided. That evidence took over two weeks to measure. You never get to talk with the person making the dispute resolution decision. The initial response from Paypal was to side with the fraud committed by the seller and close the dispute. I called Paypal twice after they sided with the seller fraud. The first person refused to reopen the dispute. The second person correctly reopened the dispute. You never get to talk to the Paypal dispute "judge" to make sure they understand the evidence. The first anonymous Paypal "judge" response did not address the evidence. It's as if they didn't at all understand the evidence and just skipped it. Anonymous backroom blackbox "judges" in the Paypal dispute resolution have so far been horrible.
This is not the first time that I have experienced fraud from a seller on AliExpress. I ordered 500g of what was supposed to be Nicotinomide Riboside. It failed a basic melting point test and taste test. The seller sent a sugar. I submitted a picture of the melting point test and got my money refunded. However, the seller was allowed to continue to sell the same fraudulent product on AliExpress, so I submitted a review with pictures of the melting point test. The seller delisted the product to erase the review and relisted the exact same product on AliExpress. AliExpress allows proven fraudulent sellers to continue to use their platform. This is one reason why there are so many fraudulent sellers on AliExpress.
All 16 cells were capacity tested with an EBC-A40L tester upon receipt, and all cells tested to 85% of 280Ah advertised capacity. An average of 238Ah capacity was measured for all 16 cells.
Below is the capacity test result for cell 6 (238.1Ah measured capacity). The capacity test results for cells 5-12 are attached. The blue curve is voltage in volts, the red curve is amperage in amps, and the horizontal axis is time in hours. The capacity test results are in Ah and the energy units are Wh. The test charged the cell fully using 3.65V, followed by a 30 minute wait, followed by a discharge at 40A until 2.5V reached, then charged at the end in order not to leave the cell in a discharged state. The max charging and discharging rate for the EBC-A40L tester is 40 amps, corresponding to 0.143C for these cells.
The manufacturer specifications for these cells shows capacity degradation vs. cycle below. The horizontal axis is cycle number and the vertical axis is percent of 280Ah capacity. We see that 85% measured capacity corresponds to 2750 cycle loss. The lifetime cycles was advertised to be 4000 cycles for these cells.
Lifetime Ah is defined as the total Ah over all 4000 cycles. Percent Lifetime Ah loss of these cells = the area under the above curve out to 2750 cycles divided by the area under the curve out to 4000 cycles. Doing that calculus, Lifetime Ah loss = 73.4%. I disputed the transaction and requested a 73.4% refund based upon Lifetime Ah loss.
I paid for 8 of the cells with a credit card and 8 of the cells with Paypal. All were bought on the same day in May 2021. AliExpress dispute resolution was horrible. They resisted the 73.4% refund, sided with the seller fraud, and closed the dispute associated with each package of 4 cells. In response, I contacted my credit card company and Paypal. The credit card company, Chase, was excellent. My credit card now shows a full refund. Paypal dispute resolution has so far been horrible. Paypal completely ignored all the definitive evidence that I provided. That evidence took over two weeks to measure. You never get to talk with the person making the dispute resolution decision. The initial response from Paypal was to side with the fraud committed by the seller and close the dispute. I called Paypal twice after they sided with the seller fraud. The first person refused to reopen the dispute. The second person correctly reopened the dispute. You never get to talk to the Paypal dispute "judge" to make sure they understand the evidence. The first anonymous Paypal "judge" response did not address the evidence. It's as if they didn't at all understand the evidence and just skipped it. Anonymous backroom blackbox "judges" in the Paypal dispute resolution have so far been horrible.
This is not the first time that I have experienced fraud from a seller on AliExpress. I ordered 500g of what was supposed to be Nicotinomide Riboside. It failed a basic melting point test and taste test. The seller sent a sugar. I submitted a picture of the melting point test and got my money refunded. However, the seller was allowed to continue to sell the same fraudulent product on AliExpress, so I submitted a review with pictures of the melting point test. The seller delisted the product to erase the review and relisted the exact same product on AliExpress. AliExpress allows proven fraudulent sellers to continue to use their platform. This is one reason why there are so many fraudulent sellers on AliExpress.
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