There are so many 48V LiFePO4 batteries available, it took a while for me to select one.
I have bought PowerTechSystems batteries before (see here for a review), and so far they have been good, but I wanted to try a 19" rack form-factor for a change.
Most of the 19" rack mount format batteries seem to take two forms, one with a display, and one without.
In the end, I chose an AOLithium 51.2V 100Ah battery,, which I bought in May from Amazon for £1,279 (around 1/3 of the cost of an equivalent PowerTechSystems battery).
From the beginning it didn't go well:
The device was packed well, and came on a mini-pallet, but I only received the battery itself, even though the advert said it would contain both management and battery connection cables:
I contacted the seller via Amazon, and they said the advert did not say it included the cables, which was a lie, and said I would have to just buy the cables (for another £100), which I was reluctant to do.
I then said I want to return it, and they said because there was nothing wrong with the battery, I would have to pay for delivery to return it myself, and they would charge me a 20% restocking fee.
I complained to Amazon, and they said I could return the battery, which I was also reluctant to do, as there was probably nothing wrong with it, I just wanted the cables they were supposed to include. They said there was no choice but to return the whole thing and get a refund.
To make matters worse, because of the weight, I would have to arrange my own shipping, and Amazon would supposedly refund me.
As it is a large and high-capacity Lithium battery, not all couriers will accept them. I contacted the original couriers that delivered it, but they don't deal with consumers.
I tried several couriers, and none of them would transport the battery back.
In the end I gave up and have kept it.
The display interface isn't bad. When the BMS turns off the battery at the low voltage cut-off point (44V?), there is enough residual charge to turn it back on again with the Solar PV charge controllers attached and ready to recharge the battery.
Battery cables were difficult to find at the time, and I could only find the connections (on their own) from a company in China.
Now, it looks like several batteries use this same connection, including "Growatt" (eg from here). Note that there are two sizes one is "6mm" and one is "8mm", but I'm not sure which one these use, as I am not sure which part should be measured.
It works ok, and seems to have around the advertised capacity, however, due to the poor communication with the company itself, I will not be buying anything by AOLithium again.
