Rebuilding Shark Battery Pack

[LewTwo]

Shark Battery Pack died last summer and I am finally getting 'round-to-it" rebuilding it. BMS would not longer charge or deliver power. All cell strings are in ballance (go figure).

Cells: 14S4P Panasonic-Sanyo NCR18650GA (these are LiNiCoAlO2 cells)
Nominal Voltage: 14x3.6 = 50 Volts
Nominal Capacity: 4x3300mAh = 13.2 Ahr

Motor is a Golden Motor front hub Smart-Pie V4 which should be:
(FYI for those that do not know, the controller is built into the motor)
Open Voltage: 20-60 Volts
Rated Power: 200-400 watts
Continuous Current: 18 Amp
Max Phase current: 50 Amp
Best I can remember I have never gone over 1200 watts ... maybe never over 1000 watts ... senility is setting in.

I am trying to get all my ducks lined up for the rebuild. I have a new common port DALY 14S Li-Ion with ballance (simple version, no bluetooth, fans, etc): 1-101-14460-J15C FK05. This one is rated for max 15 Amp charge current and max 30 Amp discharge current. Two things to note about the BMS. It will NOT fit in the shark's heat sink as I had hoped. Second the balance lead pin spacing is 2.0mm (as opposed to the 2.54mm spacing of the existing balance leads connector). So I must replace the balance leads --- no big deal.

The existing pack has no fuse. I am thinking it might be wise to add one while I am at it. High voltage DC fuses are about as common as hens' teeth. What I have found is OptiFuse 58 Volt ATC/ATO blade fuses: https://www.optifuse.com/blog/p091102.php

Not available via my prefered source (Amazon) so next up is Digikey (with associated high shipping cost). I am also getting OptiFuse inline 12 AWG 32 Volt fuse holders (red for the positive lead). I have ordered 20, 25 and 30 Amp fuses thinking that 20 amp will be the optimum. Question: Am I on the right path here or am I missing something obvious

The existing pack has a useless LED power gauge and external charge port. Both will be removed and the holes blanked.

The pack was originally wrapped with cardboard, dabbled with silicon glue and lashed with fiberglass shipping tape. I plan to use 210mm (flat) heat shrink tubing. Internally I am think of using 4mm gold plated bullet connectors for the power leads rather than hard soldering. From what I have been able to find on the RC forums they should be able to handle the current .... up to about 30 Amps anyway. Comments


I smoked the stab connector during disassembly. I purchased a XT90 anti spark connector (because it was there). When I got it, I had to use two pairs of pliers and a lot of effort to separate the male from the female side ... 'tis a bit better now but not something I want to do repeatedly. I am thinking of attaching the female side to the actual pack and putting the Male connector in the mount. Then poke 'em down into the cavity of the Shark mount. FYI: I do not remove the battery on a regular basis anyway. Comments

The external power cable will have an XT60 connector (female this time). With the common port BMS it will be used for both power to the system and alternately for charging.

I am thinking of adding a XT60 configured as a 'arming conector' to the Shark mounting base. I was going to use the XT90 antispark for this purpose but the darn thing is too hard to remove.

Shirley I have missed something

 

[LewTwo]

Small disaster ... the DALY BMS will not fit inside the Shark case
In fact there is so little room inside that case I had to cut off the XT60 connectors I thought I was going to use inside the case.
At this point I am looking at glueing the BMS to the outside of the upper part of the shark case ....
this may wind up being one ugly battery.

 

[LewTwo]

Into everyone's life a little rain must fall .... this has been more like a deluge. One of the problem with rebuilding the Luna Shark battery was I need to replace the balance leads and connector (at least according to DALY). Also the Red (positive) and Black (negative) power leads were extremely stiff stranded wire. So I wanted to replace them with something a bit more flexible. That meant removing all the old leads. First the white silicon goop had to that covered the solder points had to removed ... or at least most of it by cutting and scraping. Then the leads were desolder and discarded followed by more scraping and cleaning. The the new leads were solder in place with the power leads (BNTECHGO 12 AWG Silicone Insulated Cable) on one side and the balance leads on the other. I did NOT coat the solder point with white goop. Then I put a layer of salvaged stiff insulating paper over each side help in place with crapon (polyimide BGA) tape. Finally I put a tube of shrink wrap over it (in bands). The two little wire are for a voltmeter that attaches to the positive and negative ends of the battery pack.



Then I put it in the case for a trial fit with the BMS .... here comes the rain. The DALY BMS was too thick to fit between teh battery and bottom of the case which has a large useless cavity for a motor controller. There is darn little space available inside that case. In fact I could not even find room for the XT60 connector or the 58 volt blade fuse holder. I would up carving about half the shrink wrap off to get back at the power wires and rearrange them. If the BMS would not fit inside then it would just have to go outside. I carved a rectangular hole in one side large enough to get the balance lead connector through. Then I added two more hole to run the ground out to the BMS and back in to the switch. The BMS is attached to the outside of the case with black hot glue.

The switch turned out to be one of the least of my problems. The shark normally has a charging connector (which had been replace with a XT60 years ago) opposite the key lock. I did not need that connector which happens to sit in its own little insert. It took some work, a lot of small drill holes and a coping saw to get that connector out while leaving the insert intact. Then the hole was enlarged a bit to the new switch could be inserted. Gaps were filled in with JB-Weld. So this is what I wound up with.




Those pictures were before I cut the leads and attached a XT60 Female connector. I am going to need to make a silicone flap or something to go over the balance lead hole. I do not normally ride in the rain but that is too big a gap to ignore.

The good news is that it works, is fully charged, has a switch, an actual voltage meter and Chalo can not call it a "suitcase" battery.

 

[Muramura]

what's that long small jst wire for, I have it on mine?

 

[LewTwo]

With batteries most of the time it is for a temperature sensor to be inserted in the pack.

However in this case it is connected to the positive and negative end points of the battery pack. The JST connector plugs in the back of voltmeter. That way it is ahead of the BMS so that one gets the actual battery voltage. It also has a temperature gage inside of the volt meter but I would not rely on it.
https://www.amazon.com/dp/B081PLHVJC

 

[Muramura]

With batteries most of the time it is for a temperature sensor to be inserted in the pack.

However in this case it is connected to the positive and negative end points of the battery pack. The JST connector plugs in the back of voltmeter. That way it is ahead of the BMS so that one gets the actual battery voltage. It also has a temperature gage inside of the volt meter but I would not rely on it.
https://www.amazon.com/dp/B081PLHVJC

ahhh cool good to know yeah I put a volt meter to it and it showed my volts but just wanted to be sure thanks for confirmation

 

[LewTwo]

Detail of switch. It is on the positive lead.

 

[99t4]

Shouldn't be too hard to weatherize the balance leads exit slot but I would be tempted to ensure there is sufficient slack to allow disconnecting the balance leads from the BMS in order to be able to manually measure voltages and manually balance if necessary at some point. Make lemonade from lemons!

 

[LewTwo]

Shouldn't be too hard to weatherize the balance leads exit slot but I would be tempted to ensure there is sufficient slack to allow disconnecting the balance leads from the BMS in order to be able to manually measure voltages and manually balance if necessary at some point. Make lemonade from lemons!

I am in Houston ... what is winter?
Guess I should not be so glib after February ... on the other hand there was no way I was stepping outside at those temperatures.

There is plenty (too much maybe) slack in the balance leads. I am thinking a piece of thin silicon sheet (baking mat) hot glued behind the hole and silicon glued to the end of the BMS housing. might just slit a piece and glue over the hole first.