docnjoj
1 GW
Just solder a wire to each charger terminal and put a spade lug on the end. Those should fit into the Fatpack + and - slots.
otherDoc
otherDoc
Bosch 36V fatpacks opened up
- Thread starter John in CR
- Start date
docnjoj said:
Sorry, I forgot to mention the 3rd middle slot in my original question. I can already get the positive and negative connections to touch, just due to one of them being melted together it won't slid down far enough to engage the middle one. Since it doesn't charge I'm assuming the middle connection is important.
John in CR
100 TW
Rifle said:
You just have to jump that center one to the center on the charger. That's assuming your short didn't blow the electronics board on the pack. The charger definitely need the center slot to turn on.
John
John in CR
100 TW
I thought I'd make a quick note regarding fatpack capacity. I just finished charging my 10 fatpack pack, which is in a 5p2s configuration, ie 74 volts nominal. Starting voltage was 74.3v (3.715v avg per cell, just above half full) and the ending voltage was 81.4v (4.07v avg per cell). During the charge I added exactly 6ah to the pack or 1.2ah to each pack in parallel. Assuming 3.7v is the true nominal voltage of theses VT Konions, then Bosch fatpacks definitely have at least 2.4ah of capacity.
Those who are getting only 2.1-2.2ah are probably running their packs hard enough for their packs to get warm, causing waste heat and increasing the Puckert's Effect. At under $50/ea delivered just buy a couple more packs unless you truly have no place to put them.
Doc,
My 10pack pack is back to what I am used to, which is my batteries never feel warm to the touch at all. The 2p2s pack I ran for a week and a half was definitely getting warm to the touch. If yours feel warm at all after use, then you're sacrificing capacity and life. Don't you have plenty of room behind/under your trike's seat for lots of capacity?
The one thing that could beat out the Bosch packs would be a same price sale on the Makita 3ah packs that have the Konion V cells. The extra 20% of capacity in the same size cell is nice, since on e-bike the current limit difference really doesn't come into play unless you're using too small a pack. eg My bike that was heating up the 2p2s fatpacks (4p20s cells) now has a pack consisting of 6p20s Konion V cells and the pack stays nice and cool. That 50% increase in pack size gives me a 100% increase in capacity and range by going with the V cells instead of the VT's.
John
Those who are getting only 2.1-2.2ah are probably running their packs hard enough for their packs to get warm, causing waste heat and increasing the Puckert's Effect. At under $50/ea delivered just buy a couple more packs unless you truly have no place to put them.
Doc,
My 10pack pack is back to what I am used to, which is my batteries never feel warm to the touch at all. The 2p2s pack I ran for a week and a half was definitely getting warm to the touch. If yours feel warm at all after use, then you're sacrificing capacity and life. Don't you have plenty of room behind/under your trike's seat for lots of capacity?
The one thing that could beat out the Bosch packs would be a same price sale on the Makita 3ah packs that have the Konion V cells. The extra 20% of capacity in the same size cell is nice, since on e-bike the current limit difference really doesn't come into play unless you're using too small a pack. eg My bike that was heating up the 2p2s fatpacks (4p20s cells) now has a pack consisting of 6p20s Konion V cells and the pack stays nice and cool. That 50% increase in pack size gives me a 100% increase in capacity and range by going with the V cells instead of the VT's.
John
64ragtop
100 W
removed duplicate text. BC
64ragtop
100 W
Rifle said:
Well, though it's no joy to you, at least I now know of someone else who suddenly found him or herself with an "AWWW SHUCKS!!!
(or something similar!) look and some melted metal in hand.
Best guess I can make would be some 8 or 10 gauge wire and heavy duty alligator clips.
Maybe Bosch has replacement contacts??? I would check with one of their distributors. Tell 'em that one of your former :lol: helpers just stuck the fatpack in your toolbox and laid it on a pair of needlenose pliers
- - heck, it sounds good to me. But you might be more creative with a story 
After all, we are all using these things in Bosch power tools, aren't we :wink:
ATB
BC
John in CR
100 TW
I forgot to mention that I'd be very surprised if the fuse on the positive power lead in the pack isn't blown.
John
John
yoyoman
1 kW
Does anyone have suggestions of how to keep the spade connectors in place? The pressure of the tabs keeping the spades in place doesn't feel sufficient to guarantee that they won't accidentally come out when on a super bumpy road. Actually, I'd want something to keep the connector from moving in both the upward and outward directions. Maybe strong rubber bands?
John in CR said:
I believe the battery is fine. I still rode home on it after I shorted it and the battery meter on it still works. Also, randomly mangling and jamming a spade connector in the middle slot I was able to get the battery to charge if i held it down. However, most of the random jamming I did just yielded a blinking red light, which I don't think means it is charging. That middle connection is weird. One side of it on the batteries gives the full voltage when measured from the positive terminal, but the other gives a voltage a bit above half. Neither side gives anything when measured from the negative terminal though. I should be able to figure it out once i get some wires, but if anyone has already figured out please share. I guess it could be as easy as just having a good connection between the battery and charger instead of a mangled piece of metal
but I feel like it could matter which side it touches.yoyoman said:
I used weak rubber bands and they worked fine as long as gravity was helping, i.e. the spade connectors were coming in from the top. I switched to strong rubber bands because I just happened to have some of those big black moon shoe rubber bands laying around. No problems so far. Well except for me shorting one of the batteries of course.
Ok, just figured it out by adding some electrical tape to the mangled spade connector. As is kind of obvious from looking at the charger, the middle connector of the charger can only touch the side of the middle connection on the battery that is closest to the positive terminal. I have to have a brick on top the charger for it to charger though. Thinking something still needs to be done about that melted connection if I want to keep the charger unmodifidied for my other normal batteries. Anyone want to buy a nearly new, only ridden twice, recently shorted, but fully function Fatpack for 40 bucks? I'm thinkin' probably not. I guess I'll just be chargin' ghetto until my money situation becomes more sure.
John in CR
100 TW
Rifle said:
Just open up the damaged pack and one good pack. Remove the circuit board from the damaged pack. Connect the red and black mains from the damaged pack to the red and black mains of the one with the good board, which will give you a double fatpack and charge normally.
You sound like me, not the type to fool with warranty claims. Why not combine all of your parallel packs into 1 with just one circuit board for charging? Removing the board and covers saves a lot of space. I charge my 10 pack with 2 Bosch chargers in series. Two circuit boards remain on the chargers and all I have is a 2 wire cable going to my pack for charging. My packs stay on my bikes, so I wire in a 2 way female connection on my pack as a charging port with a matching male on the charger cable. When I pull in I just plug in and turn on the timer (for extra protection), and my bike is always ready to go with minimal charging hassles.
John
docnjoj
1 GW
Hey John in CR. I am going to just be running 1S4P on the Trike for starters. That shouldn't overload the fatpacks. I want to keep them whole for a while to make sure they work. Soon, however................ 
I have to mount them vertically on the side of the center support as there is not much room under my seat mainly due to the rear suspension. If I do take them apart I can probably mount 6-8 of 'em.
otherDoc
I have to mount them vertically on the side of the center support as there is not much room under my seat mainly due to the rear suspension. If I do take them apart I can probably mount 6-8 of 'em.otherDoc
docnjoj
1 GW
It just dawned on me that when I go to connectors (Andersons) on my 4 fatpacks to the Bosch charger do I need to connect each of the 4 middle cut-off circuits in // to the charger or can I get away with just 1 to cut off the charger at the first battery voltage. They will be charged in //. I thought I knew this but now I am not so sure?
oterhDoc
oterhDoc
John in CR
100 TW
docnjoj said:
That middle connector is just to signal the charger that it's ok to charge (pack not too hot), so I'm sure you're fine just connecting one while charging all 4 in parallel. Those 2 outside slots go directly to the power leads on the battery, so you really wouldn't be charging any different than I do with the 1 one board mounted on the 3 prongs of the charger and the + and - going to the batteries. You'd just have the circuit boards still mounted to the other packs doing nothing instead of in a box on the shelf. They have no way to stop the charging current from flowing.
John
docnjoj
1 GW
Thanks John in CR
otherDoc
otherDoc
TPA
10 kW
Just thought I'd point out that the Microsoft Live (now bing) discount is 12% today.
I have not seen 12% there in quite some time.
I have not seen 12% there in quite some time.
TPA
10 kW
The discount is now up to 14% for those of you keeping score.
docnjoj
1 GW
It figures! They won't even respond to my 8% purchase. Well, if I need more Fatpacks I know where to look! Thanks!
otherDoc
otherDoc
stiffi
100 W
Hey, sorry to be so late to the part on this, but...RoughRider said:the charger is not charging it...
I had a dead one come from Maxtool also. They told me they'd replace it, if I sent the pack to them at MY cost. I told them to stuff it. Instead I filed a dispute with Amazon and got 100% of my money back, plus I kept the dead pack.
Then...I used an old SLA charger to try to charge the pack. I just cut the connector off the charger and stuck the bare leads right into the + and - slots on the pack. I left it on there for about 1o minutes. The pack got really hot, so I got scared and pulled it off the charger.
After it cooled down, I put it on the Bosch Charger and Voila! It charged normally, all the way up to the 3 bars.
So, now I have an extra pack. I used it in my 4 Fatpack battery pack and it seems to work fine!
I am converting my Giant NRS 2 to an e-bike, probably with the Ezee rear kit from ebikes.ca.
I need to mount the battery in the frame (no rack or fenders), so I'll probably get a custom frame bag from http://www.epicdesignsalaska.com/.
The best way to assemble a triangle shaped battery seems to be using 18650 or 26650 cells, as the finished battery would be about 70mm wide, fitting well inside a custom frame bag.
And the best 18650 cells seem to be from the Bosch Fatpacks. However I will need to discard everything but the cells, so I'm wondering how hard it will be to dismantle the individual cells from the packs ? Most people here seem to be using the sub-packs intact, I can't do that.
Also, I'll go the 48V route. I haven't decided yet between 13s9p or 14s8p. I'll have to get 6 fatpacks. 13s9p will get me 48V/11Ah or thereabouts, should be enough as I always pedal with a moderate effort at least. I'm thinking 13s will ge me enough speed (need about 25mph) and be easier on the motor/controller ?
I need to mount the battery in the frame (no rack or fenders), so I'll probably get a custom frame bag from http://www.epicdesignsalaska.com/.
The best way to assemble a triangle shaped battery seems to be using 18650 or 26650 cells, as the finished battery would be about 70mm wide, fitting well inside a custom frame bag.
And the best 18650 cells seem to be from the Bosch Fatpacks. However I will need to discard everything but the cells, so I'm wondering how hard it will be to dismantle the individual cells from the packs ? Most people here seem to be using the sub-packs intact, I can't do that.
Also, I'll go the 48V route. I haven't decided yet between 13s9p or 14s8p. I'll have to get 6 fatpacks. 13s9p will get me 48V/11Ah or thereabouts, should be enough as I always pedal with a moderate effort at least. I'm thinking 13s will ge me enough speed (need about 25mph) and be easier on the motor/controller ?
jkirkeboe said:
The fatpack spot welds are uber-burly. I haven't torn one off yet, but I wouldn't be surprised if it's not only hard to do, but that the penetration may be so integrated you might cause cell damage. Sure others will chime in. They are much more burly than the Makita welds though that's for sure.
pwbset said:jkirkeboe said:
Ahhh yes... I see. Dremel goes through those like butter.
What I'm more worried about is getting the cells out of their red plastic housing. Can they be pushed out somehow or does one need to cut open everyting ? That will be quite time-consuming...
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