Could i have some pointers on refining my diy bike light?

[Ehaze]

not sure what that means but im not using any dyno or generator , just 3p3s lipo cells in holders connected to a 20w 12v led light..

[Ehaze]

one thing that might be of concern is it is getting cold and my 2 hour trail rides will be in 40 f of below , wondering how dangerous that can be to the system , i know most of the time my phone or garmin will just die , but they use tiny batteries connected to some protection , all i have is a 5amp fuse and and an led light ?

[Renate]

not sure what that means...

That was humor. Historically, bike lights have been horrible.

[Ehaze]

When i was young we didnt even have lights , just used our eyes , now i can make a light so powerful i have to worry about blowing up ;p

[Kasper]

I found this company on alibaba:
General Electronics Battery Co
http://www.gebattery.com.cn/

I've probably made about 5 orders from them, LiPo pouches and packs of 18650s, all of which came with PCM (protection modules).  They've been easy to deal with, answered technical questions quickly, and haven't said 'no' yet.  They have fulfilled requests for specific LiPo pouch sizes, 18650 pack layout, specific model of higher temperature 18650s and they got UN38.3 certification when requested.

I tested the PCM for the 18650s in the hot sun, using a spare car battery and it passed.

If you want custom packs, you could try them.  If you just want PCM, they might do that too. 

Could also check https://www.batteryspace.com/, I haven't dealt with them much but their ad sounds nice:
"Total solution for Portable Power since 1995.
Products are designed , assembled & Quality Controlled in USA. All products are shipped from California"

[AaronD]

I found this company on alibaba:
General Electronics Battery Co
http://www.gebattery.com.cn/

I've probably made about 5 orders from them, LiPo pouches and packs of 18650s, all of which came with PCM (protection modules).  They've been easy to deal with, answered technical questions quickly, and haven't said 'no' yet.  They have fulfilled requests for specific LiPo pouch sizes, 18650 pack layout, specific model of higher temperature 18650s and they got UN38.3 certification when requested.

I tested the PCM for the 18650s in the hot sun, using a spare car battery and it passed.

If you want custom packs, you could try them.  If you just want PCM, they might do that too. 

Could also check https://www.batteryspace.com/, I haven't dealt with them much but their ad sounds nice:
"Total solution for Portable Power since 1995.
Products are designed , assembled & Quality Controlled in USA. All products are shipped from California"

Alibaba (or was it Aliexpress?  I can never keep them straight) has enough naively-designed-to-a-price chinesium time bombs on it to stay well away from.  So anything associated with them carries the same reputation by default.  That doesn't mean that everyone with that association is necessarily evil, but they do have some extra work to do to make themselves credible.

Some more "devil's advocate" points:

• "Never saying no" could mean that they don't know what they're talking about, or they assume that you don't, or both.  You're probably not actually getting what you think you're getting, if they ALWAYS say yes to everything.  (ask for the physically impossible, get a "yes" answer, and "something" arrives soon after...)
• "Getting a certification when asked" could also be fake.  Just scan an official logo, slap it on your thing, and claim that it's certified.  Easy!  If you want paperwork, then that's similarly easy to forge.
• "Testing the one unit that you got" isn't proof that the next one will perform similarly.  One data point is never proof of anything.  It could be that the entire production run is good, or that could be the one unit that worked by accident, or anything in between.

So, what assurance do they give that their stuff is actually good, and how well-set are they to follow through on that, or to suddenly and conveniently disappear or hide behind international boundaries?

International law requires a huge political mess to enforce, straining relations on a global scale, and carries a remote but real possibility of war.  Most countries will let a lot slide before they go that far, and so it's practically the wild west for individual consumers buying from overseas, and most sellers know it.

[Kasper]

I found this company on alibaba:
General Electronics Battery Co
http://www.gebattery.com.cn/

I've probably made about 5 orders from them, LiPo pouches and packs of 18650s, all of which came with PCM (protection modules).  They've been easy to deal with, answered technical questions quickly, and haven't said 'no' yet.  They have fulfilled requests for specific LiPo pouch sizes, 18650 pack layout, specific model of higher temperature 18650s and they got UN38.3 certification when requested.

I tested the PCM for the 18650s in the hot sun, using a spare car battery and it passed.

If you want custom packs, you could try them.  If you just want PCM, they might do that too. 

Could also check https://www.batteryspace.com/, I haven't dealt with them much but their ad sounds nice:
"Total solution for Portable Power since 1995.
Products are designed , assembled & Quality Controlled in USA. All products are shipped from California"

Alibaba (or was it Aliexpress?  I can never keep them straight) has enough naively-designed-to-a-price chinesium time bombs on it to stay well away from.  So anything associated with them carries the same reputation by default.  That doesn't mean that everyone with that association is necessarily evil, but they do have some extra work to do to make themselves credible.

Some more "devil's advocate" points:

• "Never saying no" could mean that they don't know what they're talking about, or they assume that you don't, or both.  You're probably not actually getting what you think you're getting, if they ALWAYS say yes to everything.  (ask for the physically impossible, get a "yes" answer, and "something" arrives soon after...)
• "Getting a certification when asked" could also be fake.  Just scan an official logo, slap it on your thing, and claim that it's certified.  Easy!  If you want paperwork, then that's similarly easy to forge.
• "Testing the one unit that you got" isn't proof that the next one will perform similarly.  One data point is never proof of anything.  It could be that the entire production run is good, or that could be the one unit that worked by accident, or anything in between.

So, what assurance do they give that their stuff is actually good, and how well-set are they to follow through on that, or to suddenly and conveniently disappear or hide behind international boundaries?

International law requires a huge political mess to enforce, straining relations on a global scale, and carries a remote but real possibility of war.  Most countries will let a lot slide before they go that far, and so it's practically the wild west for individual consumers buying from overseas, and most sellers know it.

Good points.  While we are on the subject, do you know any good options in North America?  I wouldn't trust any company from anywhere but I have a little more faith in local sources.  A few examples why it is foolish to trust anyone would be volkswagen emissions scandal, theranos and flint city water.

Working with locals makes it a little easier to enforce some kind of penalty for wrong-doing but that doesn't mean it'll undo the problem it caused.

Just for the record, I haven't requested anything impossible, just specific sizes, layouts, connectors, cells and thermistor.  I've tested at least 1 from each batch.  The high temp cells had the model I requested printed on them, not sure who printed it but it's better than having the wrong model printed on it.

[Renate]

Visual is one thing, but you ought to check screen grabs to see if the actual data written is fuzzy.
(Of course) I recommend by AdbGrab.exe (in the sig).
If you see something that looks like JPEG artefacts (but it's not, because it's PNG) that could be the "High Contrast text".