Stealthy charging while travelling and at work

C

cwah

100 MW
Joined
Jul 24, 2011
Messages
4,256
Location
Between paris and london
Hello,

I've been considering a stealthy way to charge at work and while travelling. I'm currently using this one:
http://www.ebay.co.uk/itm/Precision-Compact-DC-60V-3A-Adjustable-Digital-Switching-Power-Supply-110-220V/141389291960?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20140122125356%26meid%3D0e8f8efe322a47b885852b05e518a364%26pid%3D100005%26prg%3D20140122125356%26rk%3D2%26rkt%3D6%26sd%3D311068842937&rt=nc

It's nice and lightweight, but not so compact. And not waterproof either.

I've been thinking about most of my time at work, starting from 9am to 6pm. So about 9 hours. For travelling it would be the same, better to have a big battery pack and charge while resting at night rather than bringing a massive power supply and wait for hours...

This one does seem good enough for my need:
http://www.mouser.com/ProductDetail/Mean-Well/HLN-80H-54A/?qs=QHrm%2FgeNk%252bifkzx4V7GUFg%3D%3D

Only 500g but 80W charging... It's low power but bear in mind that resting outside is about 10 hours so I can expect about 800W charging every time...

Good thing is... that it's so light I can keep it inside my battery pack. And use a cable extension like this one:
http://www.amazon.co.uk/dp/B005OLC3U0?psc=1

So for about 500g more, I'd have an integrated charger in my battery, that I can bring anywhere!!

Isn't that a great idea? :mrgreen:
 
I like the idea in some respects :D

For work, it's great since it is cheap, quiet and small. But for travelling, it will not be as great. You will likely wait over an hour to get 80Wh of charge, which may be enough to limp home if within 5 miles. :?

True, it is smaller and lighter than some other LED supplies out there, and more convenient to carry around. But when it comes to getting the job done, will it?

My work charger is a Mean Well HLG. It's heavier at over 2.5 lbs, but I only use that at work and don't carry it around unless I am going on a long trip where I will need it for opportunity charging. At 240W, it's 3X the output and less than 3X the weight.

Too bad there isn't a charger without compromise on size and power.
 
I don't see any chargers in this thread. Just power supplies.

I have a typical 240w alloy shell charger here, set for the same voltage. It weighs 800 grams complete with the iec lead. Something worth a quid, so you could leave one at work rather than carry it. You can get similar in plastic housings which would weigh considerably less.

Don't charge with power supplies, you will burn.
 
I've been charging with power supply for a very long time... why wouldn't that work?

And bmsbattery charger are too loud to be used anywhere. It sounds like a turbine lol.

Yes small and light is my motto. I also have a 300W power supply that I could carry with me if required.
 
cwah said:
I've been charging with power supply for a very long time... why wouldn't that work?

And bmsbattery charger are too loud to be used anywhere. It sounds like a turbine lol.

Yes small and light is my motto. I also have a 300W power supply that I could carry with me if required.
Click to expand...

Charging with a power supply is fine if you know what you are doing. Just like running packs without BMS. It is just that you, as a person, need to replace the functions that power supplies do not have. End of charge cutoff is easy enough if you have a watt meter of some sort while paying attention.

I have a routine. I know how many Wh I need to put in and generally how long that takes on my PS. I then have a time target and check watt meter display every 20 minutes or so. Once the current is below .15A, I pull the plug. It's the same thing that a legit charger does but I'm SURE it gets done in my case. There's no guarantee that a mass produced bulk charger will always perform that function properly. It's certainly not as smart as a human. (and we need to be clear that not all chargers are the same, I give my Satiator MUCH more trust than my EMC-1000)
 
Yah. Watt he said re the "Satiator" charger. And re "stealthy charging", from Satiator specs:
Fan Free Efficiency
The power electronics were carefully designed to reach 95% efficiency at full load, eliminating the need for a fan to get rid of waste heat and keep things cool. no more buzzing fan noise and no risk of charger meltdowns if the fan fails.
Click to expand...
 
cal3thousand said:
cwah said:
I've been charging with power supply for a very long time... why wouldn't that work?

And bmsbattery charger are too loud to be used anywhere. It sounds like a turbine lol.

Yes small and light is my motto. I also have a 300W power supply that I could carry with me if required.
Click to expand...

Charging with a power supply is fine if you know what you are doing. Just like running packs without BMS. It is just that you, as a person, need to replace the functions that power supplies do not have. End of charge cutoff is easy enough if you have a watt meter of some sort while paying attention.

I have a routine. I know how many Wh I need to put in and generally how long that takes on my PS. I then have a time target and check watt meter display every 20 minutes or so. Once the current is below .15A, I pull the plug. It's the same thing that a legit charger does but I'm SURE it gets done in my case. There's no guarantee that a mass produced bulk charger will always perform that function properly. It's certainly not as smart as a human. (and we need to be clear that not all chargers are the same, I give my Satiator MUCH more trust than my EMC-1000)
Click to expand...
I think if the battery pack has a BMS, then it can be charged with a power supply. The BMS will stop the charging when the cell/cells reaches the desired/set maximum voltage. Am I correct?
 
Hehe... "if you know watt you're doing". (Rules out about 99% of the world.)
 
LockH said:
Hehe... "if you know watt you're doing". (Rules out about 99% of the world.)
Click to expand...

Very true! That's why I'm not on Facebook advocating this to Joe Q Public. :wink:
 
The satiator doesn't do anything my power supply doesn't do.

I set charge to 80% most of the time and by a turn of a potentiometer I can easily adjust to 95% whenever I want.

I weekly check for cells to cells consistency on top charge and discharge. If there are too much difference I manually charge cells. when cell behave very similarly for a while I review them less and less frequently.

I think my method is way more safe than normal charger as it can't know when a specific cell overcharge (ie satiator) and rely on bms for verification.

You know what? I had one battery when went over a big rain, and bms popped. Nothing I can do about it apart from fearing the bms may damage the cells!
 
"The satiator doesn't do anything my power supply doesn't do." Maybe not yet (I bought version one of Cycle Analyst, currently on version three). One "problem" might be any users forgetfulness (remembering to twiddle X knob at Y time).
 
cwah said:
The satiator doesn't do anything my power supply doesn't do.
Click to expand...

Sorry, but that is NOT true. Not now, not ever.

Does your power supply roll back current when internal temperature gets too high to protect itself?
Does it handle multiple chemistries and voltage profiles quickly and easily enough that your wife can use it?
Does your power supply cut charge at the end of the cycle?
Does your power supply have a minimum start voltage to prevent charging the wrong pack or a partially shorted pack?
Is you power supply certified with these ratings: ul 1012, csa c22.2 no. 107.2, ce / iec 60335-1/2-29 ?
Is your power supply IP65 rated?
Is your power supply capable of 95% efficiency?

I am a proponent of using power supplies for charging in the right hands, but I will NEVER claim they even hold a candle to the Satiator's features and build quality.
 
what I really mean is that my power supplies does everything I need it to do... and the satiator doesn't do it better for my needs.

What I need is:
- reliable power supply. to date it has been very reliable
- compact. The satiator is no more compact.
- adjustable easy between 80% charge and 95% charge easily. The satiator does it a bit better but no real difference.

The other points would matter to other people, and many would probably choose it for its range of features... but I don't care about switching with other batteries easily and I'm not ready to pay 3 to 6 times what I've paid for ip67 rated or certified power supply.

For me to paid this much more, it would need to be significantly better in the points that makes the difference to me. Which is smallness or something that would simplify my life to track cell level life (eg. Like the new speedict with cell level bluetooth tracking)
 
cwah said:
what I really mean is that my power supplies does everything I need it to do... and the satiator doesn't do it better for my needs.

What I need is:
- reliable power supply. to date it has been very reliable
- compact. The satiator is no more compact.
- adjustable easy between 80% charge and 95% charge easily. The satiator does it a bit better but no real difference.

The other points would matter to other people, and many would probably choose it for its range of features... but I don't care about switching with other batteries easily and I'm not ready to pay 3 to 6 times what I've paid for ip67 rated or certified power supply.

For me to paid this much more, it would need to be significantly better in the points that makes the difference to me. Which is smallness or something that would simplify my life to track cell level life (eg. Like the new speedict with cell level bluetooth tracking)
Click to expand...

Fair enough! :D
 
Electronics connected to AC power at work must be NRTL listed (Nationally Recognized Testing Lab). (Rules vary somewhat by location). UL is one example of an NRTL.

That lets out the BMSBattery chargers and many other low cost chargers and power supplies. They are not legal because they are not tested to safety standards for electrical construction.

Some Meanwell supplies are listed, but not all. The LED supplies from Meanwell that I've looked up are listed.

The Satiator is listed.

Laptop power supplies are generally listed. But they rely on components inside the battery pack to regulate charging.

The Satiator has many significant advantages over power supplies - it has many safety features that a power supply by itself does not have, it has readouts and auto shutoff that a power supply lacks. It is rated for moisture and vibration beyond what most power supplies are. It has built in AC cord socket and built in thermal protection which most power supplies lack. The Satiator has lead resistance compensation which allows it to charge more quickly than a regular power supply (by raising the voltage to compensate for voltage loss in the cable). The Satiator has updatable firmware which power supplies don't have, so it continues to improve. It is designed to be a battery charger from the start so many things about it are somewhat different than for a power supply.

I charge with a power supply too, but to make a power supply be similar to a Satiator requires a lot of external circuitry and programming. Even then it would not have some of the features the Satiator has built in.
 
I thought a charger watched current fall away as the voltages equalised, just as a normal well regulated power supply would allow. Then at a threshold around 10% of full current, they drop the current right down to a trickle lower than the cells would take if allowed to, such as if using a normal regulated supply. This final stage of very low current and constant cell level voltage is not achieved with a normal psu. The normal psu allowing too much current during the final stage of charge. This threshold in an alloy shell charger is set near the middle of the box, and is why you specify the cell chemistry being used when ordering one, rather than just a voltage.

It all seems to make sense to me, but I have only glanced at the subject in passing. If any peers can educate me, please do for the threads sake.
 
Lithium chargers regulate voltage, limit current, and when the current falls low enough must shut the charging current completely off, unlike most chemistries. Lithium batteries don't accept trickle charging.

Advanced chargers like the Satiator measure the current and adjust for wiring resistance, raising the charging voltage to achieve the proper voltage AT THE BATTERY whereas a power supply or lower quality charger will allow the voltage at the battery to fall lower by the IR drop in the wires. This slows charging.
 
Thanks alan. I thought as much. As usual, a proper charger and bms is better in every way. Lighter, safer, less bother and cheaper. There is far to much faffing around on this forum when you consider how many readers are newbies in need of guideance. I would say needless faffing around, but it's much worse. It's faffing around to add more boxes more expensise more weight more bother and remove safety features. It's quite insane to share such ideas with most readers. It's no surprise that people come here for battery adice then burn their places down. The educated are far outnumbered by those that come here for help, and end up giving it.

Quite sickening
 
Received today my smallest power supply HLN I can keep at work:
2015-05-06%2020.31.58.jpg


You can see it side by side with my other one. Both are fanless.

The smallest one is about the side of 1 and half can of coke and charge at 80W. Considering I stay in average 9h at work, I expect 700wh to be feed in my battery, which is slightly more than my commuting power usage (600wh)

The one next to it can charge up to 180W, so double power but double size... however, why get bigger when I can get smaller for my needs? :)
 
do they harass you at work for charging? or is this just because of the noise of the fan in your cubicle or office you share? no boxer fans blasting away into server boxes?

maybe envision the office coffee warmer that gets the heat from the transformer on your charger.

did you ever go back over to the neighborhood where your bike battery was stolen and offer the bar bouncers a reward for snitching out the guy who stole your battery?
 
No one harass me at work for charging, but it's not something people expect me to do and work relationship is more important than being able to charge at work. I work as contractor so I don't have long term job and usually have to move from place to place.

So being as stealthy as possible can only have good thing... until someday someone find a way to make these bmsbattery charger almost inaudible. And these chargers usually have life expectancy of few months to a year before failure. I don't have good experience with these chargers so even if they are cheaper I'm not sure I want to use them.

The day bmsbattery alike chargers become reliable and silent, I'd come back to them. Until then, my set up is way better 8)


No one bother about the guy who snitched my battery, and it's probably in a bin somewhere... nothing I can do about it really..
 
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