Hello,
I have positive experience with Hallobattery.
I ordered a custom built (155*310*100mm sized), 36V 20AH LiFePO4 Battery with charger.
The customer service was responsive and proactive, they accepted PayPal, discussed the connectors with me, answered in 1-2 days to all my mails correctly.
The assembly / testing was nearly three weeks (sep.9 - sep.26), then they posted it wia Singapore EMS (EX009590052SG).
(The post was crazy, spent one month in Ireland, but it is unrelated to Hallobattery, the addressing was correct.)
Finally I got the battery ~two weeks ago, fitted to the vehicle correctly, everything was fine except one thing: the fuse was quite weak and melted in the first hill. I mailed the customer service, they apologized (they got a bad serie of fuses, replaced with good ones since then).
So in the last days of Autumn I enjoyed my vehicle (e-scooter, 1000W), everything looks fine.
Hallobattery is recommended by me.
Saman