Battery dead after 4/5 months?

-- NEWBIE ALERT --

Hi all,

Bought an E-bike kit from Aliexpress (https://www.aliexpress.com/item/33043692896.html?spm=a2g0s.9042311.0.0.7cc04c4dtS7xYR, to be precise) with a 48v 20ah 18650 Samsung cell battery. Haven't opened/used it since I received it in july, shipping took like 8 weeks.

The coves came along and I didn't get around to my project, also I had to wait on my frame to come in. Today I connected the battery to the control unit and LCD for the first time and nothing happens. The battery lits up, but only when I press the 'on' button. The charger says it's charged. The LCD display doesn't light up. The motor doesn't turn on, either.

See a quick vid here: https://drive.google.com/file/d/15mfbA7Bk3W7ROtQMA6CFTBN595gZqAx2/view?usp=sharing

I'm worried that I either left the battery uncharged for too long and it died on me or that I've somehow turned this battery into a bomb.

What should I do? Any tips?

Thanks, y'all. Love the forum!

- C

Lithium batteries are usually shipped with 50% or less charge, to minimize the risk of them catching fire. The BMS drains power from the battery to keep itself active. The rest is simple subtraction. When I bought Ping batteries, they came with the BMS unplugged to avoid what you have experienced.

LeftieBiker said:

Lithium batteries are usually shipped with 50% or less charge, to minimize the risk of them catching fire. The BMS drains power from the battery to keep itself active. The rest is simple subtraction. When I bought Ping batteries, they came with the BMS unplugged to avoid what you have experienced.

Click to expand...

Thanks for your reply! What should I do now? Should I reset the BMS?

CamielJansen said:

LeftieBiker said:

Lithium batteries are usually shipped with 50% or less charge, to minimize the risk of them catching fire. The BMS drains power from the battery to keep itself active. The rest is simple subtraction. When I bought Ping batteries, they came with the BMS unplugged to avoid what you have experienced.

Click to expand...

Thanks for your reply! What should I do now? Should I reset the BMS?

Click to expand...

No, that likely won't work. You can try disconnecting it and charging the cells individually with a lithium cell charger, or if they can still charge with the BMS disconnected, that alone might work. You just need to charge them enough for the BMS to recognize them as live cells and go back to - hopefully - doing its job properly. Don't be too surprised, though, to find one or more damaged cells.

CamielJansen said:

. The charger says it's charged. The LCD display doesn't light up. The motor doesn't turn on, either.
C

Click to expand...

Unless you have a very unique charger, i have never seen one that speaks !
So,..how do you know it is charged ? ...have you used a volt meter to check it ?

Where the part in the video where you press the center button on the three button handlebar switch? That turns on that model of LCD.

I made that mistake on my first ebike kit. Turned on the battery, no power til I pressed the on/off switch built into the LED display, Seen others make same mistake.