Basic LiPo Charging

Batteries, Chargers, and Battery Management Systems.

Basic LiPo Charging

Postby jkbrigman » Tue Jan 24, 2012 10:37 pm

The purpose of this thread is to bootstrap the concept of charging LiPo from nothing to something, using pictures.
eRecumbent. 9C 2810, 6-FET,CA,18S3P LiPo, Kenda Kwest. 33mph max 12.8Wh/mi (22mph avg) Phat Bike Commuter HS3540, 6-FET, 18S3P LiPo, Schwalbe Marathon 47mph max 25 Wh/mi (28mph avg) Basic LiPo Charging Thread , Add Throttle to Multispeed Bike
dogman: "I bet if you just don't ride like a jerk, you can do whatever you want up to the speed where everybody looks at you like this. :shock: "
tomjasz: "Romans go full dork. They could give a hoot what 'Merkins do."
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Re: Basic LiPo Charging

Postby jkbrigman » Tue Jan 24, 2012 10:39 pm

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Unboxing the iCharger 106:
eRecumbent. 9C 2810, 6-FET,CA,18S3P LiPo, Kenda Kwest. 33mph max 12.8Wh/mi (22mph avg) Phat Bike Commuter HS3540, 6-FET, 18S3P LiPo, Schwalbe Marathon 47mph max 25 Wh/mi (28mph avg) Basic LiPo Charging Thread , Add Throttle to Multispeed Bike
dogman: "I bet if you just don't ride like a jerk, you can do whatever you want up to the speed where everybody looks at you like this. :shock: "
tomjasz: "Romans go full dork. They could give a hoot what 'Merkins do."
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Re: Basic LiPo Charging

Postby jkbrigman » Tue Jan 24, 2012 10:47 pm

pwr_supply.jpg
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15V 10A Power Supply: 150W total. It's a surplus switching power supply to power my two-meter Ham Radio.
It's sat around doing nothing for over 10 years, so I can't really ascribe a "cost" to it. If you duplicated it today you might spend $35-$50.
Should work just fine to power the balancing charger.
Last edited by jkbrigman on Tue Jan 24, 2012 11:23 pm, edited 1 time in total.
eRecumbent. 9C 2810, 6-FET,CA,18S3P LiPo, Kenda Kwest. 33mph max 12.8Wh/mi (22mph avg) Phat Bike Commuter HS3540, 6-FET, 18S3P LiPo, Schwalbe Marathon 47mph max 25 Wh/mi (28mph avg) Basic LiPo Charging Thread , Add Throttle to Multispeed Bike
dogman: "I bet if you just don't ride like a jerk, you can do whatever you want up to the speed where everybody looks at you like this. :shock: "
tomjasz: "Romans go full dork. They could give a hoot what 'Merkins do."
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Re: Basic LiPo Charging

Postby jkbrigman » Tue Jan 24, 2012 10:49 pm

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Opening the iCharger 106 Box
eRecumbent. 9C 2810, 6-FET,CA,18S3P LiPo, Kenda Kwest. 33mph max 12.8Wh/mi (22mph avg) Phat Bike Commuter HS3540, 6-FET, 18S3P LiPo, Schwalbe Marathon 47mph max 25 Wh/mi (28mph avg) Basic LiPo Charging Thread , Add Throttle to Multispeed Bike
dogman: "I bet if you just don't ride like a jerk, you can do whatever you want up to the speed where everybody looks at you like this. :shock: "
tomjasz: "Romans go full dork. They could give a hoot what 'Merkins do."
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Re: Basic LiPo Charging

Postby jkbrigman » Tue Jan 24, 2012 10:52 pm

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From the left, across the top:
Temp Sensor, Rubber Feet, Battery Bulk Charge Cable (with alligator clips), USB cable, larger battery clips, tiny CD with firmware, then the charger.
Power input to the charger is the looped cable on the left of the enclosure. It will plug into the 150W power supply.
eRecumbent. 9C 2810, 6-FET,CA,18S3P LiPo, Kenda Kwest. 33mph max 12.8Wh/mi (22mph avg) Phat Bike Commuter HS3540, 6-FET, 18S3P LiPo, Schwalbe Marathon 47mph max 25 Wh/mi (28mph avg) Basic LiPo Charging Thread , Add Throttle to Multispeed Bike
dogman: "I bet if you just don't ride like a jerk, you can do whatever you want up to the speed where everybody looks at you like this. :shock: "
tomjasz: "Romans go full dork. They could give a hoot what 'Merkins do."
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Re: Basic LiPo Charging

Postby jkbrigman » Tue Jan 24, 2012 10:55 pm

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The cable as it came with the charger. The alligator clip ends are supposed to charge the Turnigy battery. But that battery has 4mm bullets.
I will have to remove the alligator clips and replace them with 4mm bullet connectors. That will give me a "1 brick charging cable"
The 7-conductor balancing cable will plug into the side of the charger, and the charger plug into the 150W power supply.
eRecumbent. 9C 2810, 6-FET,CA,18S3P LiPo, Kenda Kwest. 33mph max 12.8Wh/mi (22mph avg) Phat Bike Commuter HS3540, 6-FET, 18S3P LiPo, Schwalbe Marathon 47mph max 25 Wh/mi (28mph avg) Basic LiPo Charging Thread , Add Throttle to Multispeed Bike
dogman: "I bet if you just don't ride like a jerk, you can do whatever you want up to the speed where everybody looks at you like this. :shock: "
tomjasz: "Romans go full dork. They could give a hoot what 'Merkins do."
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Re: Basic LiPo Charging

Postby jkbrigman » Tue Jan 24, 2012 10:58 pm

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The modified cable. You can see the bullet connectors with heat shrink that replaced the alligator clips.
One is the male "banana plug" and the other is the 4mm receptacle.
Each one will plug into the 4mm encased connectors of the battery, and into the OUTPUT of the power supply.
This is how the one brick will be charged.
Notice the power supply pushbutton is lit and the balancing charger is on. When you power it on and select LiPo charging,
it defaults to a 2A charge rate.
eRecumbent. 9C 2810, 6-FET,CA,18S3P LiPo, Kenda Kwest. 33mph max 12.8Wh/mi (22mph avg) Phat Bike Commuter HS3540, 6-FET, 18S3P LiPo, Schwalbe Marathon 47mph max 25 Wh/mi (28mph avg) Basic LiPo Charging Thread , Add Throttle to Multispeed Bike
dogman: "I bet if you just don't ride like a jerk, you can do whatever you want up to the speed where everybody looks at you like this. :shock: "
tomjasz: "Romans go full dork. They could give a hoot what 'Merkins do."
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Re: Basic LiPo Charging

Postby jkbrigman » Tue Jan 24, 2012 11:03 pm

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Everything hooked up.
The balancing leads are plugged into the balancing connector. This is a JST-XH 7-conductor connector
The bulk power leads go to the banana jacks on the side of the charger.
eRecumbent. 9C 2810, 6-FET,CA,18S3P LiPo, Kenda Kwest. 33mph max 12.8Wh/mi (22mph avg) Phat Bike Commuter HS3540, 6-FET, 18S3P LiPo, Schwalbe Marathon 47mph max 25 Wh/mi (28mph avg) Basic LiPo Charging Thread , Add Throttle to Multispeed Bike
dogman: "I bet if you just don't ride like a jerk, you can do whatever you want up to the speed where everybody looks at you like this. :shock: "
tomjasz: "Romans go full dork. They could give a hoot what 'Merkins do."
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Re: Basic LiPo Charging

Postby jkbrigman » Tue Jan 24, 2012 11:07 pm

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The complete rig in operation charging 1 6S1P "brick" of LiPo. It took 2 hours to balance-charge the battery to capacity. The little fan would come on only 1 minute out of about every 15 minutes. I could not sense the balancing charger or the battery heating up at all, so I did not use the temperature sensor. I was very happy charging at only 2A charge rate, as this is .1Cmax (.1 x 20C). Very slow charging is said to prolong the life of the pack.

Toward the end of the 2 hours, the LCD charging current readout on the balancing charger started dropping. At the end of two hours, the charger shut off automatically.

Balancing charger on the left. About $75 from HK
LiPo 5Ah 6S brick. About $45 from HK
15V 10A Power Supply - made years ago, "no cost"
2 4mm Bullet connectors and heat shrink, about 20 cents.
$130 bucks shipped to get to the point of charging 1 LiPo brick. I would not call this "cheap". The charger and LiPo brick took weeks to get, shipped from Hong Kong.

I can't run the bike on only one brick, so this battery is very incomplete. To produce a complete battery for the bike, I will need more bricks (that's the research part of this project), wiring, connectors, and at some point, a "BMS": Battery Management System, to monitor all the cells while they are discharged on the bike.

I also need more wiring: parallel charging harnesses for the high-current as well as the balancing leads. Then I need a series "discharging harness" that can connect to the controller to provide 72v to the controller on the bike. Oh, and an enclosure. I still have a long way and many $$ to go before I'm turning a bike wheel electrically....
eRecumbent. 9C 2810, 6-FET,CA,18S3P LiPo, Kenda Kwest. 33mph max 12.8Wh/mi (22mph avg) Phat Bike Commuter HS3540, 6-FET, 18S3P LiPo, Schwalbe Marathon 47mph max 25 Wh/mi (28mph avg) Basic LiPo Charging Thread , Add Throttle to Multispeed Bike
dogman: "I bet if you just don't ride like a jerk, you can do whatever you want up to the speed where everybody looks at you like this. :shock: "
tomjasz: "Romans go full dork. They could give a hoot what 'Merkins do."
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Re: Basic LiPo Charging

Postby nomad85 » Wed Jan 25, 2012 1:18 am

Nice photos :-)
If you run a discharge cycle how many mah do you get out of that turnigy?
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Re: Basic LiPo Charging

Postby neptronix » Wed Jan 25, 2012 1:35 am

If you use a lot of lipo, you won't regret the investment in the iCharger. Remember that you are forgoing the cost of a BMS when you go lipo - that saves you some $.

I have about $1200 and i spent about $108 on my iCharger 1010b+. So put that into perspective :)

Check out the logview software included with the iCharger when doing discharges. best tool to weed out the dud lipo packs, ever.
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Re: Basic LiPo Charging

Postby dogman dan » Wed Jan 25, 2012 6:30 am

Good work. We sometimes forget others might need a tutorial on the simplest things. I'll go add this one to the lipo noob thread links.
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Re: Basic LiPo Charging

Postby Spacey » Wed Jan 25, 2012 6:54 am

I have a good tip for that charger, I use the 1010B+ and sit it on a lump of metal. Really helps keep the discharge/balancing nice and cool.
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Re: Basic LiPo Charging

Postby Allex » Wed Jan 25, 2012 1:24 pm

What about auto balancing during a ride?
If you have a balance harness connected to all cells, should't all of the cells connected in parallel keep the same voltage?
Maybe the principle is the same when charging?
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Re: Basic LiPo Charging

Postby jkbrigman » Wed Jan 25, 2012 11:05 pm

nomad85 wrote:Nice photos :-)
If you run a discharge cycle how many mah do you get out of that turnigy?


nom: Thanks for the photo props - they are originally 5 megapixel taken with HTC Droid Eris, resized to 640x440 or so.
I haven't run a discharge cycle yet - that's what I plan to do, and use the software neptronix talked about to "see" how the cells behave.

Your .sig says your Trek extracycle can do 45 mph on 72v 10Ah LiPo?!?!? Whoa.....
eRecumbent. 9C 2810, 6-FET,CA,18S3P LiPo, Kenda Kwest. 33mph max 12.8Wh/mi (22mph avg) Phat Bike Commuter HS3540, 6-FET, 18S3P LiPo, Schwalbe Marathon 47mph max 25 Wh/mi (28mph avg) Basic LiPo Charging Thread , Add Throttle to Multispeed Bike
dogman: "I bet if you just don't ride like a jerk, you can do whatever you want up to the speed where everybody looks at you like this. :shock: "
tomjasz: "Romans go full dork. They could give a hoot what 'Merkins do."
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Re: Basic LiPo Charging

Postby jkbrigman » Wed Jan 25, 2012 11:08 pm

Allex wrote:What about auto balancing during a ride?
If you have a balance harness connected to all cells, should't all of the cells connected in parallel keep the same voltage?
Maybe the principle is the same when charging?


Allex;
Conceptually, a balance harness during discharge would help with that, but that's not the only factor. During discharge, the internal resistance of the cell (a physical property of the cell's construction) determines the characteristics of the cell during discharge. So a balance harness during discharge won't buy you anything.

The way we're handling that is either through a "bulk" Low Voltage Control (LVC) that shuts off the controller if the pack voltage gets too low, or an HVC/LVC board, like methods sells. ggoodrum also has BMS systems you can add to the pack that'll give the same LVC/HVC features....

JKB
eRecumbent. 9C 2810, 6-FET,CA,18S3P LiPo, Kenda Kwest. 33mph max 12.8Wh/mi (22mph avg) Phat Bike Commuter HS3540, 6-FET, 18S3P LiPo, Schwalbe Marathon 47mph max 25 Wh/mi (28mph avg) Basic LiPo Charging Thread , Add Throttle to Multispeed Bike
dogman: "I bet if you just don't ride like a jerk, you can do whatever you want up to the speed where everybody looks at you like this. :shock: "
tomjasz: "Romans go full dork. They could give a hoot what 'Merkins do."
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Re: Basic LiPo Charging

Postby jkbrigman » Wed Jan 25, 2012 11:09 pm

Spacey wrote:I have a good tip for that charger, I use the 1010B+ and sit it on a lump of metal. Really helps keep the discharge/balancing nice and cool.


Thanks Spacey! I have some steel I can use for that. I was also thinking about just a nearby fan blowing on the charger(s)....
eRecumbent. 9C 2810, 6-FET,CA,18S3P LiPo, Kenda Kwest. 33mph max 12.8Wh/mi (22mph avg) Phat Bike Commuter HS3540, 6-FET, 18S3P LiPo, Schwalbe Marathon 47mph max 25 Wh/mi (28mph avg) Basic LiPo Charging Thread , Add Throttle to Multispeed Bike
dogman: "I bet if you just don't ride like a jerk, you can do whatever you want up to the speed where everybody looks at you like this. :shock: "
tomjasz: "Romans go full dork. They could give a hoot what 'Merkins do."
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Re: Basic LiPo Charging

Postby jkbrigman » Wed Jan 25, 2012 11:12 pm

dogman wrote:Good work. We sometimes forget others might need a tutorial on the simplest things. I'll go add this one to the lipo noob thread links.


Thanks man, I appreciate the good word, and thank you for adding the link to the noob thread!

I'll be putting up more pics this weekend - of the discharge and logging software and of a basic home-made charging harness.
I've got to put up some more pics of the bike, but I need a cassette removal tool and a couple of the washers before I can get things working right....

JKB
eRecumbent. 9C 2810, 6-FET,CA,18S3P LiPo, Kenda Kwest. 33mph max 12.8Wh/mi (22mph avg) Phat Bike Commuter HS3540, 6-FET, 18S3P LiPo, Schwalbe Marathon 47mph max 25 Wh/mi (28mph avg) Basic LiPo Charging Thread , Add Throttle to Multispeed Bike
dogman: "I bet if you just don't ride like a jerk, you can do whatever you want up to the speed where everybody looks at you like this. :shock: "
tomjasz: "Romans go full dork. They could give a hoot what 'Merkins do."
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Re: Basic LiPo Charging

Postby nomad85 » Thu Jan 26, 2012 12:13 am

jkbrigman wrote:
nomad85 wrote:Nice photos :-)
If you run a discharge cycle how many mah do you get out of that turnigy?


Your .sig says your Trek extracycle can do 45 mph on 72v 10Ah LiPo?!?!? Whoa.....


Yeah without a truck to draft behind it maxed out around 42mph assuming favorable conditions though :)
That battery is no more thanks to a bad bulk charger :cry: Now that better charging (ecity) options exist I am considering reviving the bike. I have 1 good zippy 5AH pack left, I asked about the turningy to compare the capacity to help decide which variant from HC to go with.
E-bike#2- Trek Xtracycle 45 mph top speed(@74v)
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Re: Basic LiPo Charging

Postby jkbrigman » Wed Feb 01, 2012 1:43 am

nomad85 wrote:Nice photos :-)
If you run a discharge cycle how many mah do you get out of that turnigy? I have 1 good zippy 5AH pack left,
I asked about the turningy to compare the capacity to help decide which variant from HC to go with.


Nom;
I went with 6S1P 20C 5Ah Turnigy. $42 from Hobby King. I looked at the 25C and up Turnigy (same specs) but they go to a larger wire gauge and 5mm bullets. Since 4mm seemed more common, I went with the smaller-rate battery - 5C didn't seem important, since I'm aiming to drain it at far less than 20C anyway. Note that my battery is a "test battery": jury's still out on whether I'm going to use LiPo into the indefinite future or not. I prefer cell_man's A123...but I need to do research just to figure out what specs I need in a battery. If a brick flames-out on me or otherwise acts to threaten home safety, I'll chicken out and go the A123....
eRecumbent. 9C 2810, 6-FET,CA,18S3P LiPo, Kenda Kwest. 33mph max 12.8Wh/mi (22mph avg) Phat Bike Commuter HS3540, 6-FET, 18S3P LiPo, Schwalbe Marathon 47mph max 25 Wh/mi (28mph avg) Basic LiPo Charging Thread , Add Throttle to Multispeed Bike
dogman: "I bet if you just don't ride like a jerk, you can do whatever you want up to the speed where everybody looks at you like this. :shock: "
tomjasz: "Romans go full dork. They could give a hoot what 'Merkins do."
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Re: Basic LiPo Charging

Postby Allex » Wed Feb 01, 2012 6:46 am

Can someone explain how a charger work.
You always see in the manuals for chargers that never use it to charge another types of batteries.

So, what is the difference between li-ion and a lipo charger, is it only that they have different cutoffs? Like 4.2 for lipo and a bit higher for li-ion? Or is it something else involved? If not than this means that you basically can connect any power source to the battery and disconnect manually when the cell hits 4.2?
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Re: Basic LiPo Charging

Postby jkbrigman » Wed Feb 01, 2012 12:30 pm

Allex wrote:Can someone explain how a charger work. You always see in the manuals for chargers that never use it to charge another types of batteries.
So, what is the difference between li-ion and a lipo charger, is it only that they have different cutoffs? Like 4.2 for lipo and a bit higher for li-ion? Or is it something else involved? If not than this means that you basically can connect any power source to the battery and disconnect manually when the cell hits 4.2?


Allex -

Answer To Your Question:

Yes, your first statement is correct: a purpose-built charger for a particular chemistry would have different voltage and current cutoffs. You cannot connect any power source to any battery and disconnect it manually. You have to match the power source voltage and current to the voltage and charge current for the battery. The purpose for this discussion topic is to show, in pictures, how to properly match a LiPo battery to a balance charger.

You can put gasoline in a diesel car or diesel in a gasoline car too. But the car will fail and not perform well. In the case of gasoline and diesel, the differences are clear because of the shared experience of many people. Now, everyone knows this is a foolish thing to do. It is similarly true with chargers and batteries, except the differences are very hard to see. Large, high-current Lithium batteries are new technology (did not exist when I got my engineering training) so I have carefully read about the experiences of the people here when charging and using LiPo, LiIon and learned from them.

Now, you can "kind of" match a charger to a battery and get some charge into a LiPo battery. But you have to be very specific about what you are doing.

Example 1: a 12V (peak 13.6V) PbSo battery charger re-used to charge a LiPo, it would "sort of" work. You could buy a 12v "nominal" LiPo pack (that would be a 3S) and charge it, but you would need to sit there and monitor the voltage and current with meters and shut it off yourself when the LiPo battery gets to the right voltage. (Cell voltage types have been extensively discussed on E-S so I won't repeat them here.) End Example

But no one here would ever advise you to do that. (any power source to a LiPo battery). LiPo can self-destruct if not properly charged. You cannot do as good a job as a computer-controlled charger or a purpose-built bulk charger. Even if you are careful and successful, you will not get good performance from the battery.

Example 2: Nissan LEAF: The Nissan LEAF is FILLED with Lithium batteries. And every cell has a BMS module monitoring the state of charge and health of that cell, and reporting that back to the car's computer system. The charging port parameters (voltage, current, control signals) are standardized by international agreement. In the case of the Nissan LEAF, it is impossible to charge the Lithium without a matched charger and without monitoring the voltage, current and temperature of the batteries. End Example.

There are those who will challenge you and say "you have left out much detail from your question - get more specific!" But I am interpreting your question in this topic thread to mean "Why are you doing all this balance-charging stuff?" I say give you a quick answer to stimulate your thinking, then you will be able to get more specific with your questions.

Explanation: Balance LiPo Charging

Balance charging lets me SEE the charge on each cell and how the pack is accepting charge current. The balance charger gives me enough information to know that my expensive $42US pack is OK.

So it's like using a pearhead socket wrench for a hammer, when you would get better, safer results using the hammer. (don't ruin a good pearhead ratchet. :-) ) Mixing LiPo with chargers not built for LiPo can ruin the battery, leave you stranded somewhere, or cause a fire and burn down your house. So the reason for careful balance charging is to monitor and properly care for your expensive pack and to protect you and your house - to be as safe as possible during charging. LOTS of cautions about this on E-S, no reason to go into that here.

This balance charger (and others like it) monitor voltage, current, temperature and state-of-charge of the battery. It has a button to switch between all the different voltages and charge currents, so it can be used with LiIon/LiPo/LiFe, NiMH/NiCd and Lead-Acid (Pb). It comes with a firmware disk. You upgrade the firmware and check/set the voltage settings when you get it. (I found mine to have both correct firmware and voltage settings.) The charger has a button where you can select each type of battery. The types it will charge are printed on the charger, underneath the big "iCharger 106B+" on the picture of the unboxing. One of the coolest features of this charger is that you can use software on your PC to monitor the rate of charge for each individual cell via the USB port.

It has a balancing port (a "standard" JST-XH connector) where wires from every cell attach, so that the charger can monitor the voltage on each cell. You have a button you can cycle through each battery type (or "chemistry") and the charger will choose the proper voltage, and more importantly, a "current taper". There is even a temp sensor port so the charger can taper off the current if the battery temperature gets too hot. If you use LiPo bricks in parallel, you can connect the entire parallel set to this charger, parallel the balancing leads, and charge the whole parallel pack.

Bulk LiPo Charging

You can buy a "bulk" charger for LiPo (say, from bmsbattery.com) and you tell them what voltage and chemistry of cell you have. they build the charger to match the desired ratings "hot off the charger". Even the bulk charger will taper off the current at the end of the charge and shut off automatically, making it safe to use with LiPo pack. It just doesn't give you as much control and information about the condition of the cells as a balancing charger does.

Many people on E-S will bulk charge most of the time, then balance charge every once in awhile, to keep all the cells in the pack at the right voltage. LiPo cells can get out of balance after awhile and one cell get "starved" for current. That will cause the pack to fail. So balance charging is a way of getting best performance out of expensive LiPo cells.

(Disclaimer: I am not affiliated with the mfr. of this charger, nor the vendor I bought it from. I'm only using it as an example of a computer controlled charger for the purposes of explanation. )
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icharger_ports.png
A three-view of the iCharger showing all ports and the display in a balance charge mode.
eRecumbent. 9C 2810, 6-FET,CA,18S3P LiPo, Kenda Kwest. 33mph max 12.8Wh/mi (22mph avg) Phat Bike Commuter HS3540, 6-FET, 18S3P LiPo, Schwalbe Marathon 47mph max 25 Wh/mi (28mph avg) Basic LiPo Charging Thread , Add Throttle to Multispeed Bike
dogman: "I bet if you just don't ride like a jerk, you can do whatever you want up to the speed where everybody looks at you like this. :shock: "
tomjasz: "Romans go full dork. They could give a hoot what 'Merkins do."
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Re: Basic LiPo Charging

Postby Rollodo » Wed Feb 01, 2012 4:09 pm

Though charging a single LiPo battery can seem that simple, things become exponentially more difficult to manage as you add more and more bricks. I didn't come across a single sentence describing time management techniques and the dangers associated with charging a LiPo in general, let alone charging in confined environments, such as an apartment. I'd love to leave the room and take a 20-minute dump while my LiPo pack is safely charging in iCharger or whatnot, but it's not what I keep reading from a number of reliable sources - here and externally. What are your thoughts on that?
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Re: Basic LiPo Charging

Postby jkbrigman » Wed Feb 01, 2012 4:53 pm

Rollodo wrote:Though charging a single LiPo battery can seem that simple, things become exponentially more difficult to manage as you add more and more bricks. I didn't come across a single sentence describing time management techniques and the dangers associated with charging a LiPo in general, let alone charging in confined environments, such as an apartment. I'd love to leave the room and take a 20-minute dump while my LiPo pack is safely charging in iCharger or whatnot, but it's not what I keep reading from a number of reliable sources - here and externally. What are your thoughts on that?


Rollodo - LiPo charging cautions are clear for all to read. This information has already been put to you by hjins in your thread:
http://endless-sphere.com/forums/viewtopic.php?f=3&t=32252&start=60

I'll post pics of multiple batteries on the charger when I get the harnesses built and the entire unit charging when I get that built also.
How's your build coming - have you found a donor bike yet?
Last edited by jkbrigman on Wed Feb 01, 2012 11:10 pm, edited 6 times in total.
eRecumbent. 9C 2810, 6-FET,CA,18S3P LiPo, Kenda Kwest. 33mph max 12.8Wh/mi (22mph avg) Phat Bike Commuter HS3540, 6-FET, 18S3P LiPo, Schwalbe Marathon 47mph max 25 Wh/mi (28mph avg) Basic LiPo Charging Thread , Add Throttle to Multispeed Bike
dogman: "I bet if you just don't ride like a jerk, you can do whatever you want up to the speed where everybody looks at you like this. :shock: "
tomjasz: "Romans go full dork. They could give a hoot what 'Merkins do."
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Re: Basic LiPo Charging

Postby Allex » Wed Feb 01, 2012 6:43 pm

jkbrigman:
Wow, thank you for all a the details!
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