Homemade Battery Packs

Batteries, Chargers, and Battery Management Systems.
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DrkAngel
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Re: Homemade Battery Packs

Post by DrkAngel » Jun 12, 2016 1:01 pm

Thread Index

DrkAngel wrote:7000 Mile Report - 2013 eZip Trailz LS

Passed 7000 miles about 100 miles ago.
Except for a brief sojourn with my 33.3V battery, 7000miles were accomplished alternating with my 2 - 25.9V 25.92Ah recycled Laptop LiPo.
I did test with the 13T motor sprocket with a 23mph cruising speed but decided was too stressful on my Laptop LiPo builds
Rough tally estimates 4500 and 4000 miles on the 2 packs.
Average of possibly 20mph+ - includes 33.3V and 13T sprocket tests, Typical cruising is 19mph+
Just did a metered recharge at .2C to 4.15V per cell with a 19.78Ah capacity on the 4500 mile pack - 1 bank dipped below 3.50V and needs repair.
(Am building 2 new packs with SONY laptop LiPo and will re-recycle present packs into electric lawnmower batteries)

Replaced OEM rear hub-wheel at 2000 miles and have had no problems with broken spokes since.
Built wheel with alloy L\R threaded hub, SS spokes and good rim.
Replaced 9T motor sprocket once, 16T ACS Southpaw freewheel once and motor chain twice.
XYD-16 motor has held up nicely but will disassemble, lube and inspect bearings and brushes.
If in reasonable condition, might retire to occasional use or sell on bike to occasional use customer?
#1 Battery (2008 dated cells) 25.9V 25.92Ah (4500 mile) got a metered .2C recharge from ~3.7V to 4.15V per cell for a 19.78Ah.
Early Spring 2014 25.9V 25.92Ah Laptop LiPo build @ 500+ cycles - 4500+ miles
7200 Mile Update
Replaced worn motor chain (3rd chain) and noise quieted considerably!
#2 Battery (2010 dated cells) 25.9V 25.92Ah (4000 mile) got a metered .2C recharge from ~3.7V to 4.15V per cell for a nearly exact 21Ah.
Late Spring 2014 25.9V 25.92Ah Laptop LiPo build @ ~500 cycles - 4000+ miles

These cells have held up admirably!!!
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

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Joachim
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Re: Homemade Battery Packs

Post by Joachim » Aug 12, 2016 2:51 am

Home build 18650 pack for e-bikes......not good not good smal laptop cells :mrgreen:
Last edited by Joachim on Oct 02, 2016 6:55 am, edited 1 time in total.

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Parallel all cells of same voltage "bank"

Post by DrkAngel » Aug 12, 2016 5:43 am

Joachim wrote:Home build 18650 pack for my e-bike.
48Volt 23Ah.
2900Mah Cells from LG: LGEBMG11865 P021A211A3.
Max discharge current 10A.

13S-8P so 104 cells in total.

Put some pvc board around the softpack before i put the battery on the e-bike.
Image
I worry that you did not connect all the cells in parallel?
Only the end banks seem properly paralleled. They would be properly BMS protected, as well as the top series, but the vast majority of the cells seem unmonitored and unprotected! ... ?

Parallel cells should be connected !
Image

13s with the 2 end banks properly paralleled leaves 11s7p unprotected.
11s x 4.20V = 46.2V
If one cell fails, in any of the unprotected 7 series banks, 46.2V ÷ 10s = 4.62V per remaining cell = Not good!
Last edited by DrkAngel on Aug 12, 2016 8:40 am, edited 1 time in total.
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

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Re: Homemade Battery Packs

Post by Joachim » Aug 12, 2016 8:39 am

looks like shit :lol:
Last edited by Joachim on Oct 02, 2016 6:49 am, edited 1 time in total.

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Re: Parallel all cells of same voltage "bank"

Post by DrkAngel » Aug 12, 2016 8:42 am

DrkAngel wrote: I worry that you did not connect all the cells in parallel?
Only the end banks seem properly paralleled. They would be properly BMS protected, as well as the top series, but the vast majority of the cells seem unmonitored and unprotected! ... ?

Parallel cells should be connected !
13s with the 2 end banks properly paralleled leaves 11s7p unprotected.
11s x 4.20V = 46.2V
If one cell fails, in any of the unprotected 7 series banks, 46.2V ÷ 10s = 4.62V per remaining cell = Not good!
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

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Re: Homemade Battery Packs

Post by Joachim » Aug 12, 2016 9:10 am

bmz is shit....pul of the tape and compleet nikkel strip comes whit it :lol:
Last edited by Joachim on Oct 02, 2016 6:51 am, edited 1 time in total.

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Re: Homemade Battery Packs

Post by Solarpower » Aug 12, 2016 9:17 am

But why did you not parallel them? One thin strip of nickel and you are good to go!

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Re: Homemade Battery Packs

Post by Joachim » Aug 12, 2016 11:33 am

The best wil be a bms for every singel cel :mrgreen: so need big cells...not the 18650 parallel shizl :roll:
Last edited by Joachim on Oct 02, 2016 6:53 am, edited 1 time in total.

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Re: Homemade Battery Packs

Post by DrkAngel » Aug 12, 2016 12:52 pm

With a parallel wire, all cells in the parallel group will register at the same voltage.
By paralleling 8p you are effectively creating a single "big" cell with 8x mAh
Last edited by DrkAngel on Oct 03, 2016 7:10 am, edited 1 time in total.
A little learning is a dangerous thing;
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There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

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Re: Homemade Battery Packs

Post by k9kruiser » Aug 28, 2016 6:53 pm

Hey Angel, should I be talking to you about a recycled battery pack?

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Re: Homemade Battery Packs

Post by DrkAngel » Aug 29, 2016 5:23 am

k9kruiser wrote:Hey Angel, should I be talking to you about a recycled battery pack?
Check Index, 1st post on page 1.
Major consideration is availability of good condition cells.
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

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Re: Homemade Battery Packs

Post by Overclocker » Aug 29, 2016 8:59 am

Image

now building up 2 packs, a 13s4p NCR-GA for bbs02. and a 17s6p ATL INR18650 for my bht motor build

Image

bonded together w/ black neutral silicone. Kapton tape as additional insulation between cells.

NCR-GA has a raised positive terminal so no need for cardboard donut insulators

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Re: Homemade Battery Packs

Post by DrkAngel » Oct 17, 2016 8:34 am

Built 3 battery "packs" recently, from recycled Lipo cells. ...

1. Battery for gaming laptop - 3s20p = 11.1V (12.6V charged) 43.2Ah Pack in sturdy CD case as an inverter pack to run an off grid gaming laptop.

2. Battery for UV floodlights - 3s12p = 11.1V (12.6V charged) 25.92Ah in GameBoy hip pack to power 3 x 12V led 9w UV flood lights (Converted 10w flood lights to 365nm UV to shine against white sheet to attract insects (moths) as part of an entomological survey)

3. Battery for Homelite Electric Lawnmower - 6s18p = 22.2V (25.2V charged) 38.88Ah to replace worn out 24V 20Ah SLA in Homelite electric mower.
I would estimate at ~350% run time compared to new SLA battery at ~45% the battery weight.
22.2V provides acceptable blade speed and was determined as optimal with the mowers 21V LVC ... good for Lipo (3.50V per cell). There is room inside battery shell for an additional 18s1p if 25.9V (29.4V charged) seems advisable.
Last edited by DrkAngel on Nov 26, 2016 7:26 am, edited 1 time in total.
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

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Re: Homemade Battery Packs

Post by 18650 E-Biker » Nov 26, 2016 3:52 am

Just Joined. I am a great admirer of Drk Angel and his posts. I have recently completed a charging and discharging board for the large amount of 18650 cells I have. Using resistors for discharging has the advantage to me of cost and the number of cells that can be discharged at one time. I realize it is not as accurate as a dedicated electronic discharger but as a comparative way to test cells, it works well for me. I have posted a humorous video at https://youtu.be/ipQ-GoXWIUM Of course it is more dangerous as the resistors get to 290 degrees F so they cannot touch anything and it requires you to stay and watch them continually while they are discharging.
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The Big Board

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Re: Homemade Battery Packs

Post by DrkAngel » Nov 26, 2016 8:12 am

Impressive!
I like that you are using multiple methods and components for each ... "task".

Just hope you have enough cells to make it worth while ...
Building batteries for:
electric bikes?
electric vehicles?
energy storage?
?
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

New & Improved - Acronym Definitions

Index - Homemade Battery Packs - Updated - November 2015

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Re: Homemade Battery Packs

Post by TheBeastie » Nov 26, 2016 8:36 am

18650 E-Biker wrote:Just Joined. I am a great admirer of Drk Angel and his posts. I have recently completed a charging and discharging board for the large amount of 18650 cells I have. Using resistors for discharging has the advantage to me of cost and the number of cells that can be discharged at one time. I realize it is not as accurate as a dedicated electronic discharger but as a comparative way to test cells, it works well for me. I have posted a humorous video at https://youtu.be/ipQ-GoXWIUM Of course it is more dangerous as the resistors get to 290 degrees F so they cannot touch anything and it requires you to stay and watch them continually while they are discharging.
Well that is impressive.
I thought I had gone a bit nutty when my cat gave me a lot of ideas and inspiration when I created my nib pack, but looking at your wall I feel a lot better now.
https://endless-sphere.com/forums/viewt ... 0#p1070861
Speed Kills Range, 10mph = 46 miles range, 20mph = 20 miles, 30mph = 8 miles range http://goo.gl/1JNL53
Over Charging Kills ur battery bit.ly/1hzWKl4
Beware of dodgy 18650 cells! youtu.be/eOshOXcSkDA
Consider PAS as your only throttle http://goo.gl/m17J9j
CO2 is core to Photosynthesis https://youtu.be/t5mvDONB6FI
Check out the Bill Gates nuclear reactor https://goo.gl/Rtky9q
10 Square Miles of solar panels = 0.12GW average power! https://goo.gl/Ub1S39

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Electric Wheel Barrel

Post by DrkAngel » Nov 26, 2016 5:09 pm

Electric Wheel Barrel-Snow Plow

New Winter project!
Found an electric wheel barrel in the dumpster behind my store.

Image
2 larger drive wheels and a smaller bogie wheel.
(Dual motors for posi-traction)
Motors engage with handlebar lever.
I traced problems to a dead 12V 22Ah SLA and a faulty 40A relay.
Replaced relay and tested with 3sRC LiPo but was disappointed at the 2 mph top speed.

Fun begins ...
At 1st I considered running at 4s for a near 3mph but ... too simple and limited.
So, Why not run at 22.2V (6s 14p 22.2V 30.24Ah fits nicely!) with a pot controlled brush controller.
Will maintain handlebar oem relay function or replace with controller on\off circuit?
Variable <1mph - >3mph

50V brush.jpg
50V brush.jpg (21.81 KiB) Viewed 2838 times
- $8
Now ... I don't have much use for a wheel barrel, but adding a plow to the front would be a great snow moving utensil!
Torque and speed should be appropriate.
Just have to add some weight. Sand or bags of salt? ... Rated for 200lb loads.
Chains?

Summer use
Mount rear 2 wheeled platform for standing on and cruising, with load, down the street.

Upper (green potion) removable by screws or add sideboards to upper portion ...

Battery compartment and motors-drivetrains remove as single component for alternate use!
LUV motor.jpg
LUV motor.jpg (30.28 KiB) Viewed 2795 times
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

New & Improved - Acronym Definitions

Index - Homemade Battery Packs - Updated - November 2015

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Re: Homemade Battery Packs

Post by DrkAngel » Dec 04, 2016 11:50 am

Did up some comparison numbers for a different thread and thought the info would be nice here also ...

I recommend a large enough pack to limit:
surge demand to ≤1C
continuous demand ≤0.5C

But, especially important with recycled cells, 1C should be rated at actual (present) capacity, rather than oem rated (new) capacity.

I lucked into some HP 12 cell packs, at nearly the same time, and was able to build a 9s12p 33.3V 31.2Ah battery, inside an eZip RMB (ReMovable Battery) pack.
Cells tested at >95% of new capacity for 30Ah+ for use with my typical (cheap) 28A controller.
  • Regeared 1 eZip for 20mph "legal" with 33.3V battery.
  • OEM eZip 1 eZip (9T motor x 20T wheel) for ~16mph @ 24.0V (450w motor output) ... 100% Torque - 100% speed
  • "My use" is 1 eZip (9T motor x 16T wheel) for ~20mph @ 25.9V (485w motor output) ... 80% torque - 125% speed
  • Regeared 1 eZip (9T motor x 22T wheel) for ~20mph @ 33.3V (625w motor output) ... 150%+ torque - 125% speed
Nearly double the torque of my typical cruising mod!
Acceleration, torque beyond maintaining speed, is nearly 200% throughout entire speed capability!


Reasonably projected MY1018z (or XYD-16) 24.0V vs 33.3V when geared for 21mph
Image
("gearing" accomplished by using comparative wheel size function) - wheel size not actually used, eZip rigs allow multiple gearing options!

Just for fun ...
33.3V with "my use" gearing (9T motor x 16T wheel) for ~26mph @ 33.3V (625w motor output) ... 110%+ torque - 162% speed
but ... tried it a few times to get it out of my system and rejected as being abusive of battery and attracting bad attention ...
Attachments
25.9vs33.3.jpg
25.9vs33.3.jpg (166.44 KiB) Viewed 194 times
Last edited by DrkAngel on Dec 10, 2016 7:00 am, edited 1 time in total.
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

New & Improved - Acronym Definitions

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Re: Homemade Battery Packs

Post by DrkAngel » Dec 04, 2016 10:23 pm

After further consideration, Snow Beast with 36V (31V LVC) controller will suffer in cold weather with my 33.3V battery!
Even with 30Ah+ battery, will likely sag to the Low Voltage Cutoff, (after some usage and when battery temp drops).

See - Batteries vs Cold

Guess it will be necessary to swap in one of my spare 24-36V+ capable controllers.
Will add a handlebar mounted volt meter to keep track of battery level.
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

New & Improved - Acronym Definitions

Index - Homemade Battery Packs - Updated - November 2015

EBike Toolbox - Bargains! $

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Re: Homemade Battery Packs

Post by DrkAngel » Dec 22, 2016 5:02 pm

............
........................
18650 Quick Sheet

Image

Cell prefixes typically indicate chemistry formulation:
............
........................
18650 Prefixes EG - xxx18650
18650 Prefix.jpg
18650 Prefix.jpg (50.42 KiB) Viewed 2516 times
Suffixes typically represent rated capacity and/or possible additional info ............
........................
18650 Suffixes EG - 18650-xx x
Last edited by DrkAngel on Dec 26, 2016 11:00 am, edited 4 times in total.
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

New & Improved - Acronym Definitions

Index - Homemade Battery Packs - Updated - November 2015

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Re: Homemade Battery Packs

Post by Hummina Shadeeba » Dec 22, 2016 5:15 pm

but those are the manufacturer rated amps. I've seen testing of the 30Q for example doing better than the lg hg2. first is rated 15 and second 20

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Re: Homemade Battery Packs

Post by 18650 E-Biker » Feb 03, 2017 5:03 pm

The 18650 Quick Sheet is fantastic and an essential tool for anyone building their own battery packs.

I have posted a new video on Youtube about my homemade battery box.
https://youtu.be/Cvm8oGUoe24

My Ezip batteries are still hanging in there and I am too Ecological (cheap) to replace them with 18650's just yet.
I have a shoutout to DRKAngel and a link to his index on the video
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13s or 14s for 48V 1000w Turbo Hub Motor - or 12s?

Post by DrkAngel » Mar 26, 2017 11:14 am

DrkAngel wrote:I picked up a similar rear wheel for about the same price, couple weeks ago. Haven't done anything with it yet.
Gotta build a 48V battery ...

Has some nice extra features:
1000w 28mph >> 750w 20mph switch! >>> Turbo!
Reverse "switch" - nice for FWD version
Scaleable PAS, based on crank speed

Sorting through my bike "boneyard" looking for appropriate match.

See -48V 1000w 26" eBike Rear Kit $152
13s or 14s battery ... ?
13s (48.1V) battery will give me a respectable 28mph in Turbo mode, but ... don't think I'll be able to resist 30mph+ by going 14s (51.48V).
14S(51.48V) is also handy considering my majority of builds are 7s(25.9V) as replacements for 24V eBikes.
Also, controller's HVC (High Voltage Cut-off) is liable to accept the higher voltage.

Which means I will pop open the controller and vet the on-board voltage and amp regulation functions.
Want to mod the switch mode back to 20mph in non-Turbo mode.
Not worried about 750w pushed to 807w or 1000w pushed to 1076w.

Pushing to 30mph will stress battery, so, rather than my typical recycled laptop cells, I will be building a hybrid pack of high capacity low surge cells in parallel with high output RC LiPo.

Will also need to mod a S-350-48 (or S-150-48) MeanWell for 13 x 4.12 = 53.56V or 14 x 4.12 = 57.68V

On the other hand, will probably make preliminary runs with a LARGE 12s (44.4V) Recycled Laptop cell battery.
More as a way to get operational ... but also to pre-test cells for final build!

Not sure if I will re-gear for pedal assist at 30mph or just lower seat and crouch behind a mini shroud-windscreen.
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

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Re: 30mph - Run or Hide?

Post by DrkAngel » Mar 27, 2017 8:45 am

DrkAngel wrote: Not sure if I will re-gear for pedal assist at 30mph or just lower seat and crouch behind a mini shroud-windscreen.
Mountain bike pedaling position requires 1000w motor output to maintain 30 mph.
Racing bike tuck pedal position requires a mere 720w to maintain 30mph.

Image

Recumbent aerodynamics requires less than 450w to maintain 30mph.

Lowered seat in combination with modest windscreen might moderate watt usage well below that of a racing bike in tuck.
Of a certainty, it will require less additional watts than I could maintain in proper mountain bike pedal position!

.
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

New & Improved - Acronym Definitions

Index - Homemade Battery Packs - Updated - November 2015

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Re: Homemade Battery Packs

Post by DrkAngel » Apr 25, 2017 6:04 am

Glorious weather ... allows my "Summer weight" batteries to "stretch their legs".
My recycled laptop LiPo cell packs struggled through the Winter.
Reduced speed and range left me fearing they had reached "end of life".

Then, hit 75ºF ... and their life began again!
Acceleration, speed and range returned!

Found up an item, specifically for my eZip RMB removable battery packs.

Floureon 7S 5000mah 25.9V 40C Lipo Battery <$60
delivered from USA


Recommended for rebuild of eZip 24V RMB battery packs.
Will fit up to 4 x 5Ah = 25.9V 20Ah vs oem 24V 10Ah (5-6Ah usable) SLA.
Every 24V controller I've ever tested works properly with 7s 25.9V battery, but a bit faster with some more torque ...

Image

eZip RMB pack internal dimensions:
150mm x 65mm x 230mm

1 $60 brick = capacity of $120 SLA pack
2x ($120) = capacity of $570 10Ah oem Lithium RMB battery
4x ($240) @ 10lb = 2x $570 10Ah oem Lithium RMB battery or 4x $120 (65lb) SLA
(4x leaves room for 22mm x 650mm x 150mm BMS)

7s BMS ≥$9
$9 20A continuous has 30A surge ...
might be adequate for 350-450watt motors in typical use?

Important!
Quality of cells not yet determined.

Sample ordered!
Will test for self-discharge and matched capacity ...
Will update after received and tested.

If of very good quality ... will add single brick to next 18650 recycled laptop cell build to improve pack IR, surge capability.
.
A little learning is a dangerous thing;
Drink deep, or taste not the Pierian spring:
There, shallow draughts intoxicate the brain,
And drinking largely, sobers us again.

I enjoy enlightening ... and enlivening the spirit of the innovators.

New & Improved - Acronym Definitions

Index - Homemade Battery Packs - Updated - November 2015

EBike Toolbox - Bargains! $

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