Alternative Lithium battery use

awol

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Sep 4, 2013
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My apologies for not noticing this request for info sooner, I don't log in so often at the moment.
Wingreen messaged me, so I thought I'd better reply on here in case anyone else is interested.
I asked the same questions on here a year or two back, and d8veh very kindly gave me all the info to make my own 4s 30 amp battery pack.
I've tinkered with electrics and electronics quite a bit in the past, but I was very green with Lipo technology then. I've since got into radio control models, so that Lipo knowledge has come in very handy since !
I connected six hobbyking 5amp 4s hard case lipos in parallel to create a 30 amp 16v battery for my two 12v outboard motors.
The output from each pack was connected via a fuse, and the 4s balance leads were connected in parallel for charging, and monitoring via the lipo alarm.
The whole lot fitted into a watertight transparent food container, with the output terminals bolted through the casing, so that the outboard croc clips connect just like a standard lead acid battery.
It's almost as bulky as an 85 amp lead acid leisure battery, but it's much lighter (4kg), and all of the 30ah can be used, so it's got almost the same useable capacity of the 85a leisure battery, used to the recommended 50% discharge level.
Hey eHomer, did you end up switching to a BC168 lipo charger? what did you think of it? anothkiwi is currently looking around for a charger so maybe let him know your thoughts on the different ones too.
 

eHomer

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Aug 20, 2012
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Hey eHomer, did you end up switching to a BC168 lipo charger? what did you think of it? anothkiwi is currently looking around for a charger so maybe let him know your thoughts on the different ones too.
Yes, I did, and I'm very pleased with it, and grateful for the advice on the forum bringing my attention to it.

The ability to charge through the balance leads is vital, I now realise, ensuring maximum charge and long life from the packs always being perfectly balanced, or put on storage charge when not in use.

As I mentioned in the previous post, now that I'm into RC models, I can also use it to maximise the life of my growing collection of smaller capacity 2s and 3s too.

Wingreen, I should have asked you what size of canoe you intend to use the battery and outboard on.

The main reason I built the Lipo pack was to power the outboard on my sit on top kayak, where weight was critical. The Lipo made the outboard a practical proposition, replacing and improving on the twin 12v sla pack that I fitted in a shoe bag, (connected in parallel, giving 28ah max, but effectively about half that for 50% discharge. This the Lipo pack gave nearly twice the ah at 16v, which gave a nice boost in power, as d8veh had suggested.

When I use my outboard in my Canadian Canoe though, Buoyancy and weight are no problem, so I use a conventional 85ah leisure battery with my Minn Kota outboard on that.

I fitted it in a portable plastic battery box, with a strong nylon shoulder strap, a 50 amp circuit breaker, a cheap Chinese wattmeter, and a cig lighter socket for my fishfinder and GPS.

The wattmeter is really useful with electric outboards, giving a very effective "fuel gauge", at an incredibly low price.
 

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Wingreen

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Jul 28, 2015
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Yes, I did, and I'm very pleased with it, and grateful for the advice on the forum bringing my attention to it.

The ability to charge through the balance leads is vital, I now realise, ensuring maximum charge and long life from the packs always being perfectly balanced, or put on storage charge when not in use.

As I mentioned in the previous post, now that I'm into RC models, I can also use it to maximise the life of my growing collection of smaller capacity 2s and 3s too.

Wingreen, I should have asked you what size of canoe you intend to use the battery and outboard on.

The main reason I built the Lipo pack was to power the outboard on my sit on top kayak, where weight was critical. The Lipo made the outboard a practical proposition, replacing and improving on the twin 12v sla pack that I fitted in a shoe bag, (connected in parallel, giving 28ah max, but effectively about half that for 50% discharge. This the Lipo pack gave nearly twice the ah at 16v, which gave a nice boost in power, as d8veh had suggested.

When I use my outboard in my Canadian Canoe though, Buoyancy and weight are no problem, so I use a conventional 85ah leisure battery with my Minn Kota outboard on that.

I fitted it in a portable plastic battery box, with a strong nylon shoulder strap, a 50 amp circuit breaker, a cheap Chinese wattmeter, and a cig lighter socket for my fishfinder and GPS.

The wattmeter is really useful with electric outboards, giving a very effective "fuel gauge", at an incredibly low price.
Not a canoe - but a small rowing boat (not bought yet but likely to be around 10 foot - once I can track a second hand one down locally). The intention is to use the boat/kit to do some fly fishing on a small (26 acre) lake where I have just joined a syndicate.
 

eHomer

Esteemed Pedelecer
Aug 20, 2012
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Not a canoe - but a small rowing boat (not bought yet but likely to be around 10 foot - once I can track a second hand one down locally). The intention is to use the boat/kit to do some fly fishing on a small (26 acre) lake where I have just joined a syndicate.
It's a difficult choice then.
I use my outboards in dinghies too, (rigid and inflatables), and the lead acid leisure battery solution is still the simplest and maybe even most cost-effective.

There's masses of spare buoyancy in dinghies, so the 18kg or so of a lead acid battery is no hardship at all, and they're still very cheap at around £60. (Even with discounts, my six Hobbyking 5ah 4s packs were nearly £20 each.)

My Lipo "lunchbox" special gave me a very useful amount of stored power in less than 4kg of weight, which was all that my small sit on top kayak could comfortably support. The 85 amp leisure battery would have been impossible, hence me previously using the pair of 14amp SLA's.

The evolution of battery technology into Lipo & Life has made electric power very practical where weight is crucial, like cycles (and rc aircraft !).

The complications of rigidly observing the charging and discharging levels and storage voltages may tip the balance though, for anyone who's usage isn't weight constrained.
 
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anotherkiwi

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The wattmeter is really useful with electric outboards, giving a very effective "fuel gauge", at an incredibly low price.
Can you give us the maximum Amps drawn by your Minn Kota?
 

flecc

Member
Oct 25, 2006
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Can you give us the maximum Amps drawn by your Minn Kota?
Pending eHomer's reply, one supplier of this range of motors rate the models as from 0.2 and 0.4 hp. At 75% efficiency that indicates around 17 to 33 Amps at 12 volts, depending on which Minn Kota model.

It will be interesting to learn eHomer's real world answer.
.
 

anotherkiwi

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Pending eHomer's reply, one supplier of this range of motors rate the models as from 0.2 and 0.4 hp. At 75% efficiency that indicates around 17 to 33 Amps at 12 volts, depending on which Minn Kota model.

It will be interesting to learn eHomer's real world answer.
.
17 Amps is 2C for an 8.5 Ah battery... And the OP has specified he won't be blasting around WOT or towing water skiers...
 
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eHomer

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Aug 20, 2012
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Can you give us the maximum Amps drawn by your Minn Kota?
My Minn Kota is an old "turbo 50", with a thrust of 32lbs, and a weight of 9kg.

My Rhino v18 electric with 18lbs thrust and weighs 3.6 kg

I'm frantically searching through all my junk for the bit of paper where I wrote down the amps at various speed levels and the duration of the various batteries.

I remember that the highest speed (5) of the Minn Kota was very power hungry compared to the lower settings.

Still searching....... :oops:
 

flecc

Member
Oct 25, 2006
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17 Amps is 2C for an 8.5 Ah battery... And the OP has specified he won't be blasting around WOT or towing water skiers...
Hence my interest, I suggested earlier that it might be possible for Wingreen to use his existing lithium batteries. For his limited needs on a small lake, the lowest power model Minn Kota used only on it's lower three power settings could make that viable, even after voltage conversion loss.

Not for continuous boating of course, but for a couple of hundred metre's out to fish, a later move to another spot and a return trip it seems possible.
.
 
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Wingreen

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Jul 28, 2015
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Thanks to all that have commented. I think I have to accept that I better just go for the "normal" solution. It'll be a Bison 40ft/lb electric motor, a SuperBatt 85Ah (or maybe 100Ah) leisure battery and a Streetwize SWIBC5 battery charger (oh, and a battery box of some sort to put the battery in). All I need now is the boat!
 
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Alan Quay

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Dec 4, 2012
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Thanks to all that have commented. I think I have to accept that I better just go for the "normal" solution. It'll be a Bison 40ft/lb electric motor, a SuperBatt 85Ah (or maybe 100Ah) leisure battery and a Streetwize SWIBC5 battery charger (oh, and a battery box of some sort to put the battery in). All I need now is the boat!
The thing with boats (on flat water) is that they don't go fast, and never go uphill. So weight is much less of a concern. An 85ah leisure battery won't cost much more than £80. That's a lot if bang for your buck. (500Wh of usable energy)

Obviously packing the thing away etc you want it to as light as possible, but in use it s no big deal.
 
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Wingreen

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Jul 28, 2015
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I'm determined to find another use for my two "frog" batteries (each of which is spec'd at 24v, 8,5ah) - especially as my old Hopper Shoppers are hardly ever used these days.
I'm having problems with my golf electric trolley so I'm thinking I have several options:
1. Find an electric trolley which requires a 24v, 8.5ah lithium battery - but which is being sold minus the battery
2. Find an electric trolley which requires a 24v, 8.5 ah lead acid battery - but which is being sold minus the battery
3. Find an electric trolley that requires lithium battery (but could be various volts and ah combinations) - but which is being sold minus the battery - and install some sort of step up/down circuitry to enable my 24v, 8.5ah Frog battery to work with it
4. Find an electric trolley that requires lead acid battery (but could be various volts and ah combinations) - but which is being sold minus the battery - and install some sort of step up/down circuitry to enable my 24v, 8.5ah Frog battery to work with it.
5. Carry out some repairs on my existing golf trolley (which runs on a 12 Volt 33AH lead acid battery) and install some sort of step up/down circuitry to enable my 24v, 8.5ah Frog battery to work with it.

Would any of the above work? Which would be easiest? Do they make sense? Are there other options?
Any help/advice/comments gratefully received
 
D

Deleted member 4366

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The only thing you need to worry about is the voltage. You can use your 24v ebike battery on any 24v golf cart. The only problem is the power. Your frog batteries can give about 15 amps - maybe 20A max. That's about 400w, which should be OK for a walk-along golf cart, but not enough for a ride-on one.

To convert their use, open the case and remove the sprung terminals, then bring the two wires out through the slots. Make a harness so that you can easily connect to the golf cart - I guess that would mean spade connectors on one end and any suitable connector, like Deans on the other end and on the battery wires.

Obviously, you need to disconnect or remove any lead batteries while the lithium one is connected.

An 8Ah lithium battery will give the same distance/time of power as a 16Ah lead one. I would have though that a single frog battery would have plenty of capacity to complete a round of golf.
 

Wingreen

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Jul 28, 2015
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The only thing you need to worry about is the voltage. You can use your 24v ebike battery on any 24v golf cart. The only problem is the power. Your frog batteries can give about 15 amps - maybe 20A max. That's about 400w, which should be OK for a walk-along golf cart, but not enough for a ride-on one.

To convert their use, open the case and remove the sprung terminals, then bring the two wires out through the slots. Make a harness so that you can easily connect to the golf cart - I guess that would mean spade connectors on one end and any suitable connector, like Deans on the other end and on the battery wires.

Obviously, you need to disconnect or remove any lead batteries while the lithium one is connected.

An 8Ah lithium battery will give the same distance/time of power as a 16Ah lead one. I would have though that a single frog battery would have plenty of capacity to complete a round of golf.
Once again - thanks d8veh.
Its a push trolley, not ride on, so that part should be OK. So.......as long as the golf trolley (motor?) is 24v then the Frog battery will be compatible (the only issue being how far it will travel) - it would not be possible to "convert" the Frog battery it so it could be used with a different Voltage DC motor.
Looking very hopeful.
However, having said I dont use the Hopper Shoppers, I've got couple of children who might start using them so, ideally, I would want to set things up so it would be easy to change use.
Its this type of battery:
frog battery.jpg

Excuse my ignorance here but....here goes. I charge it by plugging into a connection at one end - a simple kind of plug. When then fixed to my Hopper Shopper, it connects via a different (more complicated) system at the other end.
Now, given that I charge and "discharge" on my Lead Acid battery using the same connection, could I, similarly, connect the Frog Battery to my golf trolley motor using the charging connection? Charge and discharge using same connection point?
 

Wingreen

Pedelecer
Jul 28, 2015
194
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Anglesey
My frog batteries are rated at 8.5aH (8.5 amps for one hour, or 4.25 amps for 2 hours, etc). So, when you say "Your frog batteries can give about 15 amps - maybe 20A max." , do you mean that I would have to use both of them to get this result? A round of golf (at least the way I play it!) lasts about 4 hours. Although I wouldn't be using the battery for all that time (e.g.when stationary and/or when downhill etc), the maths suggests it could provide 2.125 amps for 4 hours. So, I suppose it depends on how many amps a golf trolley needs in order to move the trolley (including uphill sections). I have no real idea, unfortunately, as to how many amps a golf trolley needs.
 
D

Deleted member 4366

Guest
The amps your golf trolly needs/gets depends on its controller. I can only make a wild guess that it would be about 180W, so 7.5 amps at 24v. Your batteries are designed to run a 15 amp ebike controller with a bit of headroom, so 20 amps is the maximum you can take from it for a short time, but 7.5 amps continuous is about right for it.

You can't discharge it through the charge port. The wires inside will be too thin and most BMSs have separate charge control that only allows 5 amps to flow through. Also there could be no cut-off control when it goes flat, so you'd over-discharge it,

If you removed the battery terminals to convert it, you could always put them back again with 5 minutes soldering, but if you wanted to use the battery from one day to the next for different purposes, you'd have to make an adaptor of some sort.

Looking at it another way, the connection system on the ebike often gives problems, so, as an alternative, you could run the wires out of the battery on a short lead with a standard connector, like Deans, then run the wires out from the controller on a short lead with the matching connector so that you connect externally rather than use the pronged thing.
 

Wingreen

Pedelecer
Jul 28, 2015
194
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Anglesey
The amps your golf trolly needs/gets depends on its controller. I can only make a wild guess that it would be about 180W, so 7.5 amps at 24v. Your batteries are designed to run a 15 amp ebike controller with a bit of headroom, so 20 amps is the maximum you can take from it for a short time, but 7.5 amps continuous is about right for it.

You can't discharge it through the charge port. The wires inside will be too thin and most BMSs have separate charge control that only allows 5 amps to flow through. Also there could be no cut-off control when it goes flat, so you'd over-discharge it,

If you removed the battery terminals to convert it, you could always put them back again with 5 minutes soldering, but if you wanted to use the battery from one day to the next for different purposes, you'd have to make an adaptor of some sort.

Looking at it another way, the connection system on the ebike often gives problems, so, as an alternative, you could run the wires out of the battery on a short lead with a standard connector, like Deans, then run the wires out from the controller on a short lead with the matching connector so that you connect externally rather than use the pronged thing.
Thanks. My current golf trolley runs (badly) on a 12v, 33ah battery with a 200W motor, which is broadly consistent with your guess of 180W. Its designed to do 36 holes but just covering 18 (maybe 27) would be fine by me. My preferred option would be to use the Frog battery with my current trolley but I assume the difference in voltage would make that option unworkable.
Thanks for explaining about the charge port limitations. Looks like your idea of having an easily interchangeable set up might work. Having said that, the battery has to sit on its connector box which is attached to the bike so, when I open up the battery I will see if there is a way of keeping the current connection but just adding another in some way, which would be the option for when used on the golf trolley. (Sometimes, however, I do wish I was able to bring myself to spend money, rather than tinkering with things!)
 

Wingreen

Pedelecer
Jul 28, 2015
194
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Anglesey
Even better! - if I can find another Frog battery "holder" - like the one on the bike, then I just have to fit that to the golf trolley. Then the battery interchanges easily.
 

Wingreen

Pedelecer
Jul 28, 2015
194
59
Anglesey
If your golf trolley is 12v, it's a nogo.
Unfortunately, so far, I have failed to track down a 24v golf trolley that's sold in UK.
 

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