CSEXCEL High Performance [8-Cells 5200mAh/77Wh] Replacement Battery for KU533AA 493976-001 for HP EliteBook 8530 8730w 8730p 8530p 8530w 8540w Series Laptop Notebook Computer PCs (8530)

My interest was in the raw 18650 cells. The housing came apart really without tools, which was handy. The cells were fairly well stuck to the bottom of the housing with 2-sided tape. They are wired in a 2P4S configuration. That's a nominal 14.8V @ 5600maH rating. They are marked with some unknown branding. The marking indicates 2600maH. Since I can't find any data on these cells or even know who makes them, I can't say with certainty what the cell chemistry and parameters are. So my testing was based on kind of generic, reasonable parameters.After testing 4 of the 8 cells, they consistently delivered an average of about 2400maH, charged to 4.2V and discharged to 3.0V at 1A rate. I didn't do a long term self-discharge test and don't have the equipment to readily test cell resistance. I suspect, though, that the capacity is more important for a laptop user than the self-discharge rate unless the cells have an unusually high self-discharge rate.Without knowing the actual parameters of the pack's charging circuitry, I can't say that they aren't able to extract 2600maH per cell by discharging them below 3.0V (which is a typical lower cut-off voltage rating), but unless this is unusual cell chemistry, or they're over-discharging the cells, which will shorten the life, the 5600maH claim for the pack is probably a bit of an overstatement. This may not be the fault of the pack manufacturer -- they may be relying on the cells rated performance from the cell manufacturer.THAT SAID, in terms of value, you can't beat this pack!This product was purchased with MY OWN MONEY and nobody paid or compensated me for this review.

The batteries for this particular machine all tend to behave similarly, regardless of cell count, mah, or wh ratings... That said, this particular deal is about as good as one can expect to ever find. Excellent price, the battery, as expected, behaves just the same as any other far more expensive option, and thus far it seems to be a reliable option as well. Good things all around.

For the price this is a good battery. It came with instructions that said to set the battery by letting it fully discharge and then charge it to full. Most things I have read say NOT to do that. The battery charge according to Ubuntu jumps around, it can range from 90-100% of capacity by design.It seems to be on par with the factory battery I got with my laptop (Lenovo X200 in 2009). In the end this battery performs (or has for about 2 weeks now) like I would expect a 9 cell would by providing a solid few hours of power depending on use.

I bought two of these batteries, and they have performed consistently well. Depending on workload, I get between 4 and 6 hours from a 90% charge to a 10% charge. It is recommended to first fully charge and discharge each battery at least a couple of times for calibration, but then it's better to avoid fully charging or discharging them for the best lifetime.It was a good buy, and I will use this company's batteries in the future.

In the beginning I assumed that the battery may be need to be charged. After at least a month plug in continually it does not hold a single volt of charge. As soon as I unplug the laptop from the wall it takes about 30 seconds (max) and it dies. I usually do not write reviews but this item is a total ripoff.

I've had this battery now for about a week or so. It arrived with a charge, which lasted a surprisingly long time especially considering the gaming I was doing. Obviously, it fit my model as expected (Lenovo X201). I've let it charge all the way up and then used it until it dies to calibrate my lappy's readings. It's been doing great, about 4 hours of streaming on a single charge, or much, much longer with light use. It does increase the size of my little 12.1" machine as it sticks out the back, but I, personally don't mind that at all. (and of course, all 9 cell batteries for this model will be the same way)

I have personally run my lenovo X201 over the course of 12 hours without needing another charge. This battery may not be advertised for my laptop, but it fits perfectly and the voltages match. I went from a nearly toast 6-cell to a brand new 9-cell upon purchasing this battery, so as you may imagine, I'm rather happy to have my portability back.

[Updates]I've received new one and it fits into very well. Updated my review to five stars.I am 100% satisfied with the communication with Anna who has handled my complaint with kindness.Seems that they hear the customer's voice seriously.++++++++++++++++++++++++++++++++++++++++++++++++++Good ; It allows me two more hours with Thinkpad X201, totally up to five hours.Bad : Its size, especially the width isn't precise, a little short. It does not fit tightly into the grooves on the side of the laptop bottom and does not stay securely at one side. Actually I can insert the card into the gap. Please see the attached picture.