Small budget E-Outboard and LiFe battery ?

[Refueler]

Some may recall - I bought a dnghy / e-motor combo and the e-motor is rated as 17A max .....

I rushed out and bought a 100Ah LiFePo4 battery ... which after sorting (my Samsung A34 for somereason does not like batterys Blue Tooth) is fine. my tablet tells me condition of battery via BT etc ...

But as some pointed out - the battery size was a bit big ! .... no worries - it will be put to good use for models and other ..

The e-motor is the Aqua Marine T18 unit ...

Voltage	12 V
Power	180 WATTS (0.24 HP)
Engine thrust	up to 8.2 kg
Shaft length	60 cm
Weight	2,35 kg
Coverage	IPX4

Online it says up to 8hrs use with a 60Ah LiFePo4 ...

I have use for a 20Ah battery and ordered one, (53 euros incl delivery) ... thinking that it would be lighter - more suited to the small dinghy / budget T18 motor when not used for other purposes.

My question is - would you use a higher capacity battery if you only wanted the dinghyy for limited access to shore in sheltered waters from anchor ? I would not expect to be distance needing more than ~30mins or so to get ashore ....
I did consider 40Ah .. but the huge increase in price from the 20 makes me ask.

 

[Refueler]

OK - then plenty of views - but no replies ...

What size battery (liFePo4) do you use with your e-outboard and what is the otboard watts ? How long run do you usually get ?

 

[Chiara’s slave]

I got given a small motor, 180 watts. I tried it with a big lead acid I had hanging around. Glad I did, cos, with myself and Mrs C, who is barely 8 stone, and I’m not exactly a lardarse, it moved our inflatable at somewhat under walking pace. We were moored at The Folly at the time, and we couldn’t make against the tide flat out. I guess you haven’t got the current problem, so might well be able to use yours without finishing up inadvertently in Cowes. But size your battery for a lot of flat out use.

 

[Refueler]

I got given a small motor, 180 watts. I tried it with a big lead acid I had hanging around. Glad I did, cos, with myself and Mrs C, who is barely 8 stone, and I’m not exactly a lardarse, it moved our inflatable at somewhat under walking pace. We were moored at The Folly at the time, and we couldn’t make against the tide flat out. I guess you haven’t got the current problem, so might well be able to use yours without finishing up inadvertently in Cowes. But size your battery for a lot of flat out use.

Folly Inn ... many happy memories in the original and later building !

I knew the Landlord who was moved to another pub in latter years ... Brewery banned dancing on the tables ... sales declined ... brewery back down ... etc etc ...

Where I am - river current is barely 1kt if that ... 15ft+ boats have trolling motors on to quietly fish the river ... so the power to weight is not a problem.
Even in Swedish Archipelago - as long as weather is calmish - I don't see problem ... dinghy has oars as well ...

I admit - I do not expect any real speed out of this combo .. I may end up getting a more powerful motor - but then up goes the battery reqt.

 

[Chiara’s slave]

It will do more than a knot. I mentioned the Folly knowing you’d have a real idea about how fast or not it will go. Bank on it using 16A or a bit more, and size accordingly. For 30 mins use, the 20ah would seem to be adequate, and if it’s cheap, you could maybe have a spare. Presumably it can handle the 16A without taxing itself unduly?

 

[Refueler]

I have survived for years without any dinghy on board .... but with the advent of E-Outboards and the improvement of the budget dinghys - thought it time to look again.

Apart fron occasional anchor to shore when I get across the Baltic ... I thought about having it on standby when I fly models on the river ... normally i run my 5m Progress speedboat with its 20HP on the back ... but my idea now is to fly standing on shore ... with the dinghy as rescue standby in case model does not come back to shore !

 

[Chiara’s slave]

Sounds like a plan. We always carry a dinghy if cruising, even though it’s a bit of a pain, and we are obviously quite weight sensitive. We have an Aqua Marina Aircat and an E Propulsion motor. Its quite light, but you need either waterproofs or swim gear to use it in the sea

 

[Refueler]

Sounds like a plan. We always carry a dinghy if cruising, even though it’s a bit of a pain, and we are obviously quite weight sensitive. We have an Aqua Marina Aircat and an E Propulsion motor. Its quite light, but you need either waterproofs or swim gear to use it in the sea

I have no intention of using in any seas !! the tube diameter does not impress me ...

 

[Chiara’s slave]

I have no intention of using in any seas !! the tube diameter does not impress me ...

We’re used to getting wet, from sailing beach cats.

 

[Refueler]

My Russian wife and I ... boat in Yarmouth ... weather was atrocious ....

We were moored on the pontoons just inside of harbour breakwater.

The Avon I had was our way of getting ashore ... even though it was full to gunwhales of water - we still managed to get ashore / back to boat ...

A number of boats broke lines during the storm ... wife has never forgot !!

 

[Chiara’s slave]

It does blow, in Yarmouth. Usually when we’ve just got back, and are getting the sails down, and folding prior to coming in the harbour. It contributes to the sense of adventure.

 

[elliotmc]

I got given a small motor, 180 watts. I tried it with a big lead acid I had hanging around. Glad I did, cos, with myself and Mrs C, who is barely 8 stone, and I’m not exactly a lardarse, it moved our inflatable at somewhat under walking pace. We were moored at The Folly at the time, and we couldn’t make against the tide flat out. I guess you haven’t got the current problem, so might well be able to use yours without finishing up inadvertently in Cowes. But size your battery for a lot of flat out use.

Positively scary I would think. With the wrong wind and a full 100 amp lithium po2 battery you could have still landed up being blown all the way to Holland. 0.24 hp is produced for what use, I wonder.

 

[MikeBz]

I doubt you’re going to be running that at anything other than flat out. I interpret any “up to x hours” figures as “you probably won’t get near x hours”. 8 hours from 60Ah => 7.5A which is ~90W. We have an Elite 500W, running at <20% power might be OK to trickle along in a flat calm with no adverse current. Before splashing out on an Li battery I’d try hooking it up any battery I’ve already got and see whether the flat out speed is useful and how long it would take at that speed to cover the distance you might typically want to. That way you will have some measure as to whether it’s going to be useful and what size battery you will need.

Having read that back it’s all rather obvious, sorry…

 

[Refueler]

The motor came with the dinghy .... so its a case of seeing if its usable ..

As I said earlier - if needed - I may buy a stronger motor .;..

 

[Chiara’s slave]

Positively scary I would think. With the wrong wind and a full 100 amp lithium po2 battery you could have still landed up being blown all the way to Holland. 0.24 hp is produced for what use, I wonder.

Normally, having started 2 miles up a river, that would be quite a small risk. I daresay I could have got hold of the shore if I’d needed to.

 

[SaltIre]

I got given a small motor, 180 watts. I tried it with a big lead acid I had hanging around. Glad I did, cos, with myself and Mrs C, who is barely 8 stone, and I’m not exactly a lardarse, it moved our inflatable at somewhat under walking pace. We were moored at The Folly at the time, and we couldn’t make against the tide flat out. I guess you haven’t got the current problem, so might well be able to use yours without finishing up inadvertently in Cowes. But size your battery for a lot of flat out use.

Positively scary I would think. With the wrong wind and a full 100 amp lithium po2 battery you could have still landed up being blown all the way to Holland. 0.24 hp is produced for what use, I wonder.

I think it extremely unlikely that they could have been blown from half-way up the River Medina to Holland, no matter the type of wind.
Welcome to the forum btw.

 

[LiftyK]

I acquired a second-hand first generation e-Propulsion Spirit. What a wonderful transformation of the dinghy experience. When moving just a td briskly, it indicates about two and half hours of capacity. When it is doing its usual job of shadowing a gentle paddle boarder, it says it can keep going for 9 hours and 59 minutes. That's actually incorrect. The maximum time it can display is 9 hours and 59 minutes.

My point is, if you do not intend to zoom around then do try the smaller battery. If you need more capacity in future, you can double up the batteries.

 

[Chiara’s slave]

I acquired a second-hand first generation e-Propulsion Spirit. What a wonderful transformation of the dinghy experience. When moving just a td briskly, it indicates about two and half hours of capacity. When it is doing its usual job of shadowing a gentle paddle boarder, it says it can keep going for 9 hours and 59 minutes. That's actually incorrect. The maximum time it can display is 9 hours and 59 minutes.

My point is, if you do not intend to zoom around then do try the smaller battery. If you need more capacity in future, you can double up the batteries.

Whilst bearing in mind that a wobbling, kneel on the board newbie with a hangover will outpace a 180w motor….

 

[Egret]

Is there a formula or formulas to help relate kicker thrust in pounds - to Watts as in e-propulsion display etc - to KWh battery power taken - to square metres of underwater area - and shape water displacement - to calculate a possible speed, and whether a kicker will be sufficient for a particular purpose.

180W on the e-lite gives a gentle jog around when not in a hurry, but the 500W is useful when there is a bit of wind and tide - so it will be interesting what Refueller finds.

 

[mogmog2]

We have an Osapian 55 (which scored well in a PBO article on e outboards for peasants) - that's 25kg thrust and that drives the two of us in our Redcrest at a leisurely pace. I think 8kg is inadequate - it states it's designed for kayaks...
I only bought a small Victtron deep discharge 25Ah AGM for proof of concept* (it works well) so have only motored conservatively - I view it as an alternative to rowing rather than being all Miami Vice so it's not for everyone. Most demanding we've been is on the Dart, from The Anchorstone up to Dittisham jetty against a mild current & back (1km each way) and in Studland about 1km each way to Old Harry. It counters sensible tide at East Head too.
*My calculations (incorrect ) were that it had to be able to get us from anchor at East Head, to the beach & back- it does way more than that without stressing the battery (if done at a leisurely pace).

The reason I read this post is that I'm looking for an LFP battery to increase range even more or grunt for those occasions when leisurely isn't quite what one wants.