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Battery Replacement on Lights with Internal Li-Ion Batteries



 
 
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  #21  
Old February 8th 18, 01:56 AM posted to rec.bicycles.tech
Frank Krygowski[_4_]
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Posts: 6,329
Default Battery Replacement on Lights with Internal Li-Ion Batteries

On 2/7/2018 2:23 PM, sms wrote:
On 2/6/2018 8:48 PM, Jeff Liebermann wrote:
On Tue, 6 Feb 2018 10:52:50 -0800, sms
wrote:

My wife's Lezyne Deca 1500XXL stopped taking a charge, at all. Taking it
apart, I saw that the batteries were made in July 2015. Not too good for
it to stop working that soon. These lights don't have user-replaceable
batteries, but by removing two screws I was able to open it, and the
battery pack does have a connector on it so at least they didn't solder
it directly to the printed circuit board.


I don't see a problem.* If your wife used the light every day for
about 2 years, that would be 730 charge cycles.* That's about the
correct lifetime for a 60% DoD (depth of discharge).* See table 2:
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries


Not nearly every day. I'd estimate about 200 total charge/discharge
cycles. Something failed in the battery pack because it wasn't like the
operating time was less than when new, the pack would not charge at all.

Charging the batteries in parallel with a 2A USB charger is also about
right.* For two alleged 2800mA-hr cells in parallel, that would be
about 0.35C charge which is quite safe.

I've found that the cells that die quickly are usually helped along by
a charge circuit that overcharges the battery.* 4.2v should be the
absolute maximum.* LiIon loses about 10% of it's capacity during the
initial rapid discharge from 4.2 to 4.0V.* While I don't like losing
the 10%, the battery will last much longer if only charged to 4.0v.
Charging to 3.92v yields the best compromise between two failure
mechanisms (electrolyte oxidation and growing crud on the anode).* See
"summary" section:
http://batteryuniversity.com/learn/article/bu_808b_what_causes_li_ion_to_die


The charge voltage was correct. And of course the protection circuit in
he pack ensures that the charge voltage doesn't exceed 4.2V, regardless
of what the charging circuit voltage actually is.

It's a 2 cell 18650 pack with the batteries in parallel, and a
protection circuit board shared between the two cells. The cells are
allegedly 2800mAH, for a total of 5600mAH.


Seems rather high.* Note that batteries are tested at a 0.2C
discharge, which yields larger numbers than the usual headlight
discharge rate.* The Lezyne Deca 1500XXL claims 1500 lumens, which
also seems a bit high.* Assuming 120 lumens/watt at a nominal
3.7V/battery, that's:
*** 1500 / 120 / 3.7 = 3.4A
to run the headlight at full brightness, or 1.7A per cell.
Meanwhile, the cell capacity is tested at:
*** 0.2 * 2800 = 0.56A


This is the battery in the original pack:
http://www.gebc-energy.com/Uploadfile/pdf/ICR18650/ICR18650H3.pdf

I disassembled the pack. The batteries are completely discharged, 0V. To
me this indicates a failure of the protection circuit which normally
would not allow discharge below 2.8V.

The closest I could find
on-line was a 2x2600mAH parallel pack
https://www.amazon.com/dp/product/B003SH4BV6.


Notice that his version:
https://www.amazon.com/Tenergy-Li-ion-2200mAh-Rechargeable-Battery/dp/B002Y2LJW0/

is series connected, but claims only 2200ma-hr.* Kinda looks like the
same cells, but wired differently.* Looks like the one you purchased
might be lying about the battery capacity.* You'll find out soon
enough if the battery is discharged faster than expected.


Do any manufacturers not lie? It's a matter of degree. Tenergy is an
industrial supplier of batteries with a real building in Fremont, and
not like buying no-name batteries on Aliexpress.

Ready to buy a battery discharge tester
http://www.westmountainradio.com/cba.php
and a lux meter?
https://www.ebay.com/itm/391973339920
https://www.ebay.com/itm/401324425264

I moved the connector from the old pack to the new pack, plugged it in,
and closed it up. Seems to work fine now.


Yeah, for how long will it work?* Dig out your digital volts-guesser
and measure the EoC (end of charge) voltage.* If it's over 4.2v, that
may be why it died early.* Also, see how long it will run.* You don't
want it going out prematurely on the initial test run.* Maybe carry a
2nd headlight for the initial testing.


The charge voltage from the plug that connects to the battery was 4.19V.
I checked that before I ordered a new battery because I thought that the
problem with the light might have been with the charging circuitry.

The measured lumens by mtbr.com of the Deca Drive XXL was 1390, so they
were not using chilumens
https://www.urbandictionary.com/define.php?term=chilumen, and there
was minimal lunmenflation
https://www.urbandictionary.com/define.php?term=lumenflation.

This morning I put the light on the maximum setting and it ran for just
about exactly two hours before it stepped down the intensity.

5200*** mAH [rated]
3.7*** V [rated]
19.24*** Watt-Hours [calculated]
2.0*** Hours [measured]
9.62*** Watts [calculated]
2.6*** Amps [calculated]
1390*** lumens [measured by mtbr.com]
144.5*** lumens/watt [calculated]
3*** LEDs
48.2*** lumens/LED [calculated]

Of course the reality is that the batteries were not fully discharged
when it dropped the output, so the lumens per watt was likely quite a
bit higher.

I like the design of the Lezyne and how they use 3 LEDs to mitigate
thermal issues, as well as to give a more usable beam pattern that
includes sufficient side illumination. Definitely NOT StVZO
https://www.urbandictionary.com/define.php?term=stvzo.


Scharf's dictionary editing reminds me of this Dilbert strip:

http://dilbert.com/strip/2009-05-08

What some
people don't understand is that optics are very important in bicycle
lights where you are dealing with a limited amount of battery or dynamo
power.


What I don't understand is that you say that now, yet you've spent years
lobbying in favor of systems that shine half of their lumens at overhead
aircraft, instead of where they're really needed.


--
- Frank Krygowski
Ads
  #22  
Old February 8th 18, 07:07 AM posted to rec.bicycles.tech
Tosspot[_3_]
external usenet poster
 
Posts: 1,202
Default Battery Replacement on Lights with Internal Li-Ion Batteries

On 07/02/18 20:23, sms wrote:
On 2/6/2018 8:48 PM, Jeff Liebermann wrote:
On Tue, 6 Feb 2018 10:52:50 -0800, sms
wrote:

My wife's Lezyne Deca 1500XXL stopped taking a charge, at all. Taking it
apart, I saw that the batteries were made in July 2015. Not too good for
it to stop working that soon. These lights don't have user-replaceable
batteries, but by removing two screws I was able to open it, and the
battery pack does have a connector on it so at least they didn't solder
it directly to the printed circuit board.


I don't see a problem.* If your wife used the light every day for
about 2 years, that would be 730 charge cycles.* That's about the
correct lifetime for a 60% DoD (depth of discharge).* See table 2:
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries


Just adding to this, a lot of people don't realise LiIon batteries die
without doing anything to them. In other words, you can't just simply
count recharge cycles if they are infrequent.

https://batteryworkshop.msfc.nasa.go...att_KBugga.pdf


  #23  
Old February 8th 18, 07:56 AM posted to rec.bicycles.tech
Jeff Liebermann
external usenet poster
 
Posts: 2,908
Default Battery Replacement on Lights with Internal Li-Ion Batteries

On Thu, 8 Feb 2018 07:07:29 +0100, Tosspot
wrote:

On 07/02/18 20:23, sms wrote:
On 2/6/2018 8:48 PM, Jeff Liebermann wrote:
On Tue, 6 Feb 2018 10:52:50 -0800, sms
wrote:

My wife's Lezyne Deca 1500XXL stopped taking a charge, at all. Taking it
apart, I saw that the batteries were made in July 2015. Not too good for
it to stop working that soon. These lights don't have user-replaceable
batteries, but by removing two screws I was able to open it, and the
battery pack does have a connector on it so at least they didn't solder
it directly to the printed circuit board.

I don't see a problem.* If your wife used the light every day for
about 2 years, that would be 730 charge cycles.* That's about the
correct lifetime for a 60% DoD (depth of discharge).* See table 2:
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries


Just adding to this, a lot of people don't realise LiIon batteries die
without doing anything to them. In other words, you can't just simply
count recharge cycles if they are infrequent.

https://batteryworkshop.msfc.nasa.go...att_KBugga.pdf


That's for LiIon batteries that might be used in a space mission,
where long "storage" life, until needed, it important. Even so,
NASA's own conclusion (at end of report) does not suggest that the
cells self destruct without doing anything to them:

Lithium ion cells have thus far shown impressive storage
characteristics at low to warm storage temperatures
Over 90% capacity available at ambient and low storage
temperatures.
Retain good low temperature capability after storage.
Marginal increase in the impedance, possibly from cathode
interface.
Lithium ion batteries show good promise to meet the needs
of long-life space missions (or terrestrial applications, e,g
biomedical) but require continued validation from such
real-time tests.

The "continued validation" means:
"More research is necessary. Send funding".

What I've found in my disorganized testing is that I can throw a few
charged LiIon batteries into my dashboard glove compartment, located
to top of the dashboard where the sun can easily turn it into an oven,
cram the battery into my cell phone or flashlight, and get about 90%
of the capacity of a freshly charged battery. I've been doing such
battery rotation with cell phone batteries for about 10 years without
any problems. I've also been doing it with 18650 and 14500 flashlight
cells for about 2 years, also without any problems.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
  #24  
Old February 8th 18, 06:49 PM posted to rec.bicycles.tech
Joerg[_2_]
external usenet poster
 
Posts: 5,548
Default Battery Replacement on Lights with Internal Li-Ion Batteries

On 2018-02-07 13:05, Ian Field wrote:


"Joerg" wrote in message
...
On 2018-02-06 13:07, Ian Field wrote:


"sms" wrote in message
news My wife's Lezyne Deca 1500XXL stopped taking a charge, at all. Taking
it apart, I saw that the batteries were made in July 2015. Not too
good for it to stop working that soon. These lights don't have
user-replaceable batteries, but by removing two screws I was able to
open it, and the battery pack does have a connector on it so at least
they didn't solder it directly to the printed circuit board.

It's a 2 cell 18650 pack with the batteries in parallel, and a
protection circuit board shared between the two cells. The cells are
allegedly 2800mAH, for a total of 5600mAH. The closest I could find
on-line was a 2x2600mAH parallel pack
https://www.amazon.com/dp/product/B003SH4BV6.

I moved the connector from the old pack to the new pack, plugged it
in, and closed it up. Seems to work fine now.

My favourite is recycle bin rescues - with a £0 price tag; life
expectancy isn't something to get traumatised about.

Most laptop packs are 2 or 3P-3S, you can split them up as series or
parallel pairs A/R.



In many areas they won't let you dive into recycling bins. You'd
almost have to lie in wait, dart out and yell "Yo, don't hand over
that laptop just yet!". Otherwise when it's in there it's in there and
not coming back out.


Most don't take any notice - one that said no has the bin next to
customer service desk, reconnaissance on the way in - anything interest
and i make use of the seating and wait for the clerk to nip out.



In the country you live in maybe. In the US there may be a nasty
surprise waiting when trying to leave the store with the treasure, later
followed by a police cruiser for a ride into town but not to the
destination you intended.

--
Regards, Joerg

http://www.analogconsultants.com/
  #25  
Old February 8th 18, 08:53 PM posted to rec.bicycles.tech
Tosspot[_3_]
external usenet poster
 
Posts: 1,202
Default Battery Replacement on Lights with Internal Li-Ion Batteries

On 08/02/18 07:56, Jeff Liebermann wrote:
On Thu, 8 Feb 2018 07:07:29 +0100, Tosspot
wrote:

On 07/02/18 20:23, sms wrote:
On 2/6/2018 8:48 PM, Jeff Liebermann wrote:
On Tue, 6 Feb 2018 10:52:50 -0800, sms
wrote:

My wife's Lezyne Deca 1500XXL stopped taking a charge, at all. Taking it
apart, I saw that the batteries were made in July 2015. Not too good for
it to stop working that soon. These lights don't have user-replaceable
batteries, but by removing two screws I was able to open it, and the
battery pack does have a connector on it so at least they didn't solder
it directly to the printed circuit board.

I don't see a problem.* If your wife used the light every day for
about 2 years, that would be 730 charge cycles.* That's about the
correct lifetime for a 60% DoD (depth of discharge).* See table 2:
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries


Just adding to this, a lot of people don't realise LiIon batteries die
without doing anything to them. In other words, you can't just simply
count recharge cycles if they are infrequent.

https://batteryworkshop.msfc.nasa.go...att_KBugga.pdf


That's for LiIon batteries that might be used in a space mission,
where long "storage" life, until needed, it important. Even so,
NASA's own conclusion (at end of report) does not suggest that the
cells self destruct without doing anything to them:

Lithium ion cells have thus far shown impressive storage
characteristics at low to warm storage temperatures
– Over 90% capacity available at ambient and low storage
temperatures.
– Retain good low temperature capability after storage.
– Marginal increase in the impedance, possibly from cathode
interface.
• Lithium ion batteries show good promise to meet the needs
of long-life space missions (or terrestrial applications, e,g
biomedical) but require continued validation from such
real-time tests.

The "continued validation" means:
"More research is necessary. Send funding".

What I've found in my disorganized testing is that I can throw a few
charged LiIon batteries into my dashboard glove compartment, located
to top of the dashboard where the sun can easily turn it into an oven,
cram the battery into my cell phone or flashlight, and get about 90%
of the capacity of a freshly charged battery. I've been doing such
battery rotation with cell phone batteries for about 10 years without
any problems. I've also been doing it with 18650 and 14500 flashlight
cells for about 2 years, also without any problems.


Keep them cool and they last better. Ime, it doesn't really add up to
much because with daily usage i.e. phone, they begin to noticeably die
about the three year mark anyway. And they are a damn sight better that
NiCads!

  #26  
Old February 8th 18, 08:59 PM posted to rec.bicycles.tech
Joerg[_2_]
external usenet poster
 
Posts: 5,548
Default Battery Replacement on Lights with Internal Li-Ion Batteries

On 2018-02-06 18:56, Frank Krygowski wrote:
On 2/6/2018 1:52 PM, sms wrote:
My wife's Lezyne Deca 1500XXL stopped taking a charge, at all. Taking
it apart, I saw that the batteries were made in July 2015. Not too
good for it to stop working that soon.


Some of my bikes have dynamos that are 30 years old. They just keep
going and going and going...


Until you get to a red traffic light, to a stop sign or into a traffic
jam. The perfect spot at night to get hit by a car driver who didn't see
you because you were on the only unlit vehicle around.

I have 4-5h of juice on the road bike. If that ever drops off it'll cost
me around $20 to replace the Li-Ion battery pack.

--
Regards, Joerg

http://www.analogconsultants.com/
  #27  
Old February 8th 18, 09:08 PM posted to rec.bicycles.tech
Joerg[_2_]
external usenet poster
 
Posts: 5,548
Default Battery Replacement on Lights with Internal Li-Ion Batteries

On 2018-02-07 07:01, AMuzi wrote:
On 2/7/2018 12:06 AM, Tosspot wrote:
On 07/02/18 03:56, Frank Krygowski wrote:
On 2/6/2018 1:52 PM, sms wrote:
My wife's Lezyne Deca 1500XXL stopped taking a charge, at
all. Taking it apart, I saw that the batteries were made
in July 2015. Not too good for it to stop working that soon.

Some of my bikes have dynamos that are 30 years old. They
just keep going and going and going...


I bet the lights don't, as he peers at a collection of
CYOs[1] and a recently defunct Flat-S. Tbf the Flat S is
around 7 years old.

[1] Not one lasted 18 months, they simply aren't waterproof
imho.


My regular glass bulb lamps go 6~8 years between bulb failure in daily
use. YMMV


Ye olde 2.4W + 0.6W with a dynamo? When riding at a good clip, meaning
north of 15mph, those never lasted much longer than a month for me. Even
if they didn't blow their filament right away the bulbs turned black
inside and became dimmer than they were already to begin with. When I
was a teenager I started equipping my bikes with what the automotive
industry already understood over 100 years ago, brighter lights, a
battery and charging system. Soon the German police wanted to give me a
ticket for "non-standard" lighting. Luckily by that time I was a Dutch
resident and they had to let me go.

Those 2.4W bulbs were a joke. My bikes (after my teenage years) always
had better lighting than that. Now it's all LED on my bikes but the real
stuff with more than 500 lumens.

--
Regards, Joerg

http://www.analogconsultants.com/
  #28  
Old February 8th 18, 09:12 PM posted to rec.bicycles.tech
Joerg[_2_]
external usenet poster
 
Posts: 5,548
Default Battery Replacement on Lights with Internal Li-Ion Batteries

On 2018-02-07 08:20, Frank Krygowski wrote:
On 2/7/2018 1:06 AM, Tosspot wrote:
On 07/02/18 03:56, Frank Krygowski wrote:
On 2/6/2018 1:52 PM, sms wrote:
My wife's Lezyne Deca 1500XXL stopped taking a charge, at all.
Taking it apart, I saw that the batteries were made in July 2015.
Not too good for it to stop working that soon.

Some of my bikes have dynamos that are 30 years old. They just keep
going and going and going...


I bet the lights don't, as he peers at a collection of CYOs[1] and a
recently defunct Flat-S. Tbf the Flat S is around 7 years old.

[1] Not one lasted 18 months, they simply aren't waterproof imho.


I had one off-brand dyno LED headlight quit. Oddly enough, the LED
itself died while the light was less than a year old. The company had
stopped selling it - gee, I wonder why? - so they gave me a battery
light in exchange. Just for kicks, I replaced the dyno light's LED
myself and it still works.

But I'm not qualified to comment on waterproofing of Cyo lights. I have
a couple, but they're mounted under my handlebar bags. They don't get
very wet even on the unusual occasions when I ride at night in the rain.


That depends on the kind of rain. Sideways rain, big old fat rain,
upside down rain :-)

https://www.youtube.com/watch?v=K2ihL_FrFPs

--
Regards, Joerg

http://www.analogconsultants.com/
  #29  
Old February 8th 18, 09:20 PM posted to rec.bicycles.tech
AMuzi
external usenet poster
 
Posts: 9,767
Default Battery Replacement on Lights with Internal Li-Ion Batteries

On 2/8/2018 2:08 PM, Joerg wrote:
On 2018-02-07 07:01, AMuzi wrote:
On 2/7/2018 12:06 AM, Tosspot wrote:
On 07/02/18 03:56, Frank Krygowski wrote:
On 2/6/2018 1:52 PM, sms wrote:
My wife's Lezyne Deca 1500XXL stopped taking a charge, at
all. Taking it apart, I saw that the batteries were made
in July 2015. Not too good for it to stop working that
soon.

Some of my bikes have dynamos that are 30 years old. They
just keep going and going and going...

I bet the lights don't, as he peers at a collection of
CYOs[1] and a recently defunct Flat-S. Tbf the Flat S is
around 7 years old.

[1] Not one lasted 18 months, they simply aren't waterproof
imho.


My regular glass bulb lamps go 6~8 years between bulb
failure in daily
use. YMMV


Ye olde 2.4W + 0.6W with a dynamo? When riding at a good
clip, meaning north of 15mph, those never lasted much longer
than a month for me. Even if they didn't blow their filament
right away the bulbs turned black inside and became dimmer
than they were already to begin with. When I was a teenager
I started equipping my bikes with what the automotive
industry already understood over 100 years ago, brighter
lights, a battery and charging system. Soon the German
police wanted to give me a ticket for "non-standard"
lighting. Luckily by that time I was a Dutch resident and
they had to let me go.

Those 2.4W bulbs were a joke. My bikes (after my teenage
years) always had better lighting than that. Now it's all
LED on my bikes but the real stuff with more than 500 lumens.


For years with a Margil cover or, after a Krygowski mod with
O ring, and without a switch (always on) I have no
complaints about function or longevity. YMMV.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971


  #30  
Old February 8th 18, 09:21 PM posted to rec.bicycles.tech
Joerg[_2_]
external usenet poster
 
Posts: 5,548
Default Battery Replacement on Lights with Internal Li-Ion Batteries

On 2018-02-06 20:48, Jeff Liebermann wrote:
On Tue, 6 Feb 2018 10:52:50 -0800, sms
wrote:


[...]


It's a 2 cell 18650 pack with the batteries in parallel, and a
protection circuit board shared between the two cells. The cells are
allegedly 2800mAH, for a total of 5600mAH.


Seems rather high.



Probably a Chinese spec :-)

Just like with lights where there are lumens and then there are Chilumens.


... Note that batteries are tested at a 0.2C
discharge, which yields larger numbers than the usual headlight
discharge rate. The Lezyne Deca 1500XXL claims 1500 lumens, which
also seems a bit high. Assuming 120 lumens/watt at a nominal
3.7V/battery, that's:
1500 / 120 / 3.7 = 3.4A
to run the headlight at full brightness, or 1.7A per cell.
Meanwhile, the cell capacity is tested at:
0.2 * 2800 = 0.56A


Classic American answer: Then you need a bigger battery. On my road bike
I use eight 18650 cells, four in parallel and two of those packs in
series so the current on the cable to the front light doesn't exceed 1A,
at least not by much.

My MTB has to make do with four cells but except for short bursts on
city streets or fast county roads I drop that down from 8W to 3W or
sometimes even 1.5W in front.

I ride all roads in car traffic with lights, day and night, and then
usually at full bore. Bike paths sans DRL, singletrack with just the
front light lit so dirt bikers see me.

[...]

--
Regards, Joerg

http://www.analogconsultants.com/
 




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