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>> Home > Tags > battery voltage

battery voltage
battery life
battery mount
battery pack
battery power
battery voltage
Seeing the light by MouldBuilder Commander   Posted: 13 hours ago
Evening Doug. I have made up a couple of circuits. They both work well. I have fitted the variable resistor to your design and it works really well. The circuit components are as follows. R1=200k variable. R2= 4k7 resistor. Chip= 7555 CMOS. Capacitor after R2=10uf. Capacitor at pin 5 = 10uf. Single blue LED is 20mA with a 180r resistor. Battery voltage 6V. I have some strange results. The variable resistor works well but strangely, if I disconnect the capacitor at pin five, there is no effect to the flashing light at all. It still works well. There is also no effect if I increase or decrease the value. I am happy with the results but would like to increase the on time a little. Please can you tell me which component should be altered and whether the value rises or falls. Thanks for your help.😉

MV TEAKWOOD by RHBaker Fleet Admiral!   Posted: 3 days ago
Water trials have been delayed by trying to resolve the challenges with my HMS Brave Borderer project drivetrain. As those efforts have been halted, waiting for new components, decided to complete the Teakwood water trails. First battery trails used 8 x 1.2 Ni-Mh cells is series, giving 9.6 volts. This was unsuccessful as the battery life was only minutes. Lesson from this is not to buy cheap Ni-Mh cells from an Oriental source. Tried 2 x 7.4 Ni-Mh packs is series giving 14.8 volts. Vessel was far too fast and throttle control poorly modulated. Was thinking of fitting a voltage reducer with this battery layout so could adjust the top speed. Have done this before and it works well. When searching in my box of bits found a voltage step up increaser. Never used this before so rewired the Ni-Mh packs to parallel and adjusted the output voltage to 10 volts to see how it worked. Result is a nicely performing model with an usable top speed potential for emergency, Duration of the first run comfortable exceeded 1 ½ hours, which am satisfied with. The cells are positioned around mid hull to supplement the fitted ballast. From the pictures the model has all the grace and style of the original vessel and sails well. In conclusion, a successful project that justifies the many hours spent in building and refining the model

Charging NiMhs, one for Doug?... by RNinMunich Fleet Admiral!   Posted: 7 days ago
Evenin' Martin, Oh dear oh dear oh dear! 😲 There is some good advice above, but maybe not optimally expressed for use by a Luddite! Sorry guys but this might be a relatively long post to separate the wheat from the chaff, explode a few myths and resolve this little conundrum of Martin's! One thing at a time! NUMBER1. THE RADIO- Dear Martin: Whatever possessed a self confessed Luddite and Scrooge like you to spring a large chunk of your hard earned pension on one of the most expensive and complex RC sets on the market in the first place???? I bought a Spektrum DX6 on impulse a few years ago while strolling around Conrad here in Munich. I've regretted it ever since. In retrospect it was way too expensive >600€, and complex. It is intended for the Fly Boys, as unfortunately most sets are these days. I have still not successfully programmed it to do what I want to do, instead of what it is pre-programmed to do for helis and fixed wing aircraft. Not even with it's own Spektrum RX, let alone a 'foreign' RX like Orange. So I have not yet risked it in a model. Definitely NOT my Catalina. Since then I have bought a Turnigy I6. Which does the same as the Spektrum, works fine with my Orange RX with giro for the Catalina😉, cost only 69€ (is now available for around 33 quid😡) and within a few hours I had it programmed and tested to do all I want in my destroyer and Sea Scout.👍 In short: the Spektrum is way way way Overkill for your yacht or Fire Float or similar, where you will only ever want rudder and sail servo / winch or rudder and speed control. So flog the Spektrum and get a nice simple (and cheap😉) 2 or 4 channel set. I can't imagine you ever wanting to start building special effects into your models so 2 (max 4) channels is all you will probably ever need. Stick your Spektrum on eBay, maybe you'll get at least a 100 quid for it. If you still want to go 2.4Gig get yourself a Turnigy i6 set with RX, 6 ch but cheap enough and I can help you directly with binding and programming from experience - I have a good English manual with no Chenglish gobbledygook. If not and you still have a working 27 or 40MHz FM set (40 would be better) use that. Where you sail, all alone, who's going to bother you or be bothered? BTW: Yes the Spektrum TX IS DSM2 and DSX compatible BUT you have to tell it what you want to use!!! Frankly I think trying that with a non-Spektrum RX is risky - especially first time out and for a novice Luddite😉 NUMBER 2. THE NiMh BATTERY- Voltage is not a reliable indication of battery charge / remaining capacity. After use a battery will recover slightly when at rest and the open terminal (off load) voltage will rise, often to the nominal voltage or slightly above. This is NO indicator of remaining charge as when a load is applied the voltage will drop again rapidly, the higher the current drawn the faster the voltage drops. If it goes below 1.0V per cell the battery will be permanently damaged and never regain it's original capacity. Haverlock is dead right about batteries losing charge when not used or regularly recharged. An NiMh batt loses charge at the rate of about 1% per day so after 3 months or so you can send it to the great recycling depot in the sky and buy a new one. Periodic cycling, discharge / charge prevents / minimises this - see care hints I posted above. And yes, NiMh do have that irritating Memory effect🤔 albeit not so pronounced as with NiCads. Lipos apparently not, but I ain't seen any evidence yet - the jury is still out! Sooo - ignore the 6.37V and run the batt through a discharge and full charge cycle. If your new NiMh batt has not yet been cycled and charged I would bet that it's present capacity is about 45%. See example below (and in attached pic) of one of my new 4.8V (nom) NiMh RX batts. NUMBER 3. THE CAPACITY CHECKER - "Glorified voltmeter" ? Where did the 6.37V reading come from if not from your 'new toy'? If it is showing volts it should also be showing capacity in %age. If you received the wrong thing it's not the "bloody electrics" but the bloody nit who packed and sent it that's at fault. Before you send it back check the below😉 Send me a photo of the Checker you have and with your battery plugged in so I can see what's happening on the display. Otherwise we are all poking about in the dark (Are we back to Jules and his friend Sandy😉😲) The link I sent you was for a checker exactly the same as mine except for the labelling! As you can see in my photo, properly connected it shows the terminal voltage and the remaining capacity (charge level) of the battery pack. Forget the Nixx (=2 Ni possibilities) display, that just means 'It ain't a LiXX' (3 Li- pissibolities). Attached photo shows a brand new 4 cell NiMh RX pack 4.8V (Nominal) connected to one of my Checkers. As you can see the voltage shown is 5.19V, according to the popular 'folklore' that would seem to indicate FULL charge. Unfortunately not🤔 Capacity indication is 45% which is normal for brand new batteries in storage and transit. Explanation thereof - see above! RE: " If it can do LiPos, why not the relatively simpler NiMhs?" a) the LiPo pack has a different chemistry and construction which requires different input circuitry on the checker, b) LiPos need balancing and are fitted with Balancer Plugs which connect to the multipin connectors on the checker. Each pin connects to one cell of the LiPo so that they can be monitored individually. LiPo chargers use this to balance the cells to within 0.01V (100mV) or less by adjusting the charge / discharge currents to each cell. The checkers use this to show you the individual cell voltages and charge states. A big difference, i.e.lower V and capacity, indicates cells with faults, e.g. higher internal resistance, or a discharged pack which needs charging and balancing. NiMh packs don't usually have this facility to measure individual cells. They are thus connected to a separate input on the checker which can then only show total pack terminal voltage and capacity. BTW: if you can get it passed 'THE Management' store your battery packs in the fridge😲 The 'coolth' slows down the rate of self discharge, which is a function of the battery internal resistance, which reduces slightly with reduced temperature😉 Enough for now, back to stripping my PTB for it's Midlife Refit! Cheers, Doug 😎 PS Martin: Just saw your post about another RX. Why the hell not buy a Spektrum designed Rx guaranteed to work with their TX? Or better still; flog the Spektrum and get a nice simple Turnigy set as above, also recommended by Ron, albeit the 9 ch version. All this frigging about with 'claimed compatible' bits and pieces just wastes money and time, fogs the issue and don't prove nutt'n!

Charging NiMhs, one for Doug?... by RNinMunich Fleet Admiral!   Posted: 9 days ago
Mornin' Martin, my PTB problems will take a while to sort but I was anticipating a complete refit anyway. Soooo --- Basically Ron's right about the charger👍 Press 'Batt Type' and then 'Dec' a few times until 'PROGRAM SELECT NiMh BATT (pic one) appears in the display. Press 'Enter' and pic two should appear. Press 'Dec' so that 'NiMH CHARGE Aut' appears in display. Seems the default current is set to 0.6A in this mode. Leave it at that. If not 0.6A use the INC/DEC button to adjust it to that. Press 'Start/Enter' for more than 3 seconds and away it'll go. Charge time depends on the capacity of the battery. Rule is Capacity (C) in Ah/Charge current (I)x1.4 hours. Example; a 2Ah (2000mAh) at 0.6A would need (2/0.6)x1.4 = 4.66r hours, or about 280 minutes. The charger should stop at the right time automatically. BUT: check the capacity of your new battery with your new toy first! If it has residual capacity significantly greater than about 30% and voltage of more than 1.1V it should be fully discharged down to 1.0V minimum first. There is a function in the charger to do this. Then charge it as above with the Auto mode at 0.6A. This is to help prevent the so called memory effect. Extract from imax manual page 9- "Some rechargeable batteries have a memory effect. If they are partly used and recharged before the whole charge is accomplished, they remember this and will only use that part of their capacity next time. This is a 'memory effect' It is said that NiCd and NiMH batteries are suffering from memory effect. NiCd has more memory effect than NiMH." Don't get too charged up😉 I envy you listening to 'The Navy Lark' 😲 A Sunday afternoon delight back then. Before or after 'Desert Island Discs'? HMS Troutbridge, Capt. Poby "HENRY are you wearing odd socks?" - "No my love", Number One Sub Lieutenant (Leslie) Philips "Cor! Who threw that?", CPO (Bill) Pertwee, and "Bridge? Staaarboard Lookout Able an' when am I gonna be Leadin' Seaman Goldsteen (?) 'ere. I jus' thought you might like to know that we're 'eadin straight for the Admiral's Barge an' maybe you'd like to change course or summat"! Luvly stuff 😁 Cheers and good night from Munich, Doug 😎 PS: Well meant Haverlock but I wouldn't recommend fast charging for any battery chemistry, MAX 1A charge current for any battery, except perhaps a car battery but then Max 5A. It reduces the useful lifetime of the battery. Fast charge rates are more or less a marketing gimmick, it just means you CAN charge at higher rates without the battery exploding. Of course the manufacturers are very happy if you do do it and then have to buy new batteries more frequently because you've reduced their capacity and shortened their life. Most especially a brand new battery should NEVER be Fast charged. To get maximum life and capacity out of a new battery it should actually run through about 10 discharge / charge cycles to condition it for maximum output and minimum memory effect. Martin: check the label or packaging of your battery for 'Standard' and 'Fast' charge current! PPS: a fully charged 5 cell NiMh can be significantly above 6.0V. Up to ~6.5V, which is why I warned Martin to check the specs of his RX and any ESC. Some are rated for 5V only and go pop at 6V. That's why I only use 4 cell NiMh packs for my external RX supply. 1.2V per cell is only the nominal rating of an NiMh cell, fully or over charged they can go up to nearly 1.28V per cell.

Charging NiMhs, one for Doug?... by Westquay Fleet Admiral!   Posted: 10 days ago
Doug, Gawd bless yer , Guv'nor, I knew you'd come through with the advice on electrical stuff. My Dad would be ashamed of me as that was his game, but I could never raise interest and therefore retain any knowledge he ever imparted to me about it. A wall wart is what I've seen those little plug in the wall chargers that do 4 AAs or AAAs and charge up overnight described as, mainly by overseas chaps. They do, however become alarmingly warm sometimes, but do a good job for my camera and my wee digital radio, so I can always catch the Goons or the Navy Lark on BBC 4 Extra, or some good new music on Guy Garvey's programme on 6Music. So they work, but I have a pack, now, pre soldered, of 5 cells. My Orange Rx and servos are happy with 6Volts or so their blurb says. I'll look up a battery condition meter and get one. I just ordered a Multimeter to just do volts. Always a good adjunct to a household anyway. I have my Dad's two Avometers in their original leather cases, but can no longer get the high voltage batteries they contain. Found a miniature Avo in a smaller leather case, but don't know how to use it. I hope you can get some sense out of the words and music for the imax B6 charger. Off to eat myself (eat myself?) Eats, shoots and leaves Martin

Charging NiMhs, one for Doug?... by RNinMunich Fleet Admiral!   Posted: 10 days ago
Hi Martin, 1. What the blue blazes is a wall wart? 🤔 2. You can't do any harm to the RC gear with an under charged battery👍 But if you use it before charging it you may drive it below it's damage threshold of 1.1V per cell if you use it too much in that state. A word of warning: some RXs and ESCs don't like more than 6.0V (e.g. Action electronics/Component Shop) and a fully charged NiMh can be more than that so check the specs of your RX and ESC first! 3. Get yourself a simple battery capacity checker, see attached pics of the two I have. As you can see, they all look the same except for plastic colour and brand name. They only cost few quid and save a lot of ruined batteries and cost/heartache😉 Available from HobbyKing etc etc. They can check voltage and capacity. For LiPos they check individual cells. For NiCad or NiMh it just checks total voltage and capacity as most NiMh don't have external connections to individual cells like the LiPos do for balancing the cells. As I still have some hi power NiMh drive batteries, for ESCs that are not LiPo safe, I made a simple JR/Tamiya adaptor to connect to the monitor. In my pics you can see the % charge / capacity display. Some show only around 46% cos they are 'as delivered' with a storage charge only. Before use they need fully charging. 4. Re Charger: Just downloaded the manual - I'll get back to you on that when I've read it. Now it's 'Eat'n time' 😁 Cheers, Doug 😎

What Li-po? by RNinMunich Fleet Admiral!   Posted: 20 days ago
Hi Yngvegr, basically I agree with Flack👍 But if you want to go step by step and test it with the 540s first (will give you a Datum to compare with brushless at a later stage) then- Brushed have no problem with LiPos, or any other battery chemistry for that matter😉 For the voltage anything from 6 to 12V is fine for the 540. I have two 540s in my 135cm destroyer and she ran just fine on a 6VSLA, with a relay to switch a second one in series for 'All Ahead Emergency'! Higher capacity brings not only more sailing time but also more weight! Suggest you weigh the existing batteries and check the waterline and trim in the 'domestic test tank' before you buy the biggest batts you can find😉 If you do go LiPo don't forget to buy an appropriate charger and a Capacity Tester as well!!! Whatever you do, have fun doing it, cheers Doug 😎

H.M.S BRAVE BORDERER by RNinMunich Fleet Admiral!   Posted: 21 days ago
Evenin' Rowen, So far so good, nice job👍 Let me go through your comments one by one😉 1) "Moved the battery towards the stern and, at speed, the forefoot lifts slightly clear of the water. The plane is now almost flat. The battery is not well positioned when near the bow." Battery in the bow is almost always bad news🤔 too much weight forward of the CoG or natural balance point when planing. 2) "The 2S battery used was a 4000mAh 30C; suspect this battery does not have the capacity to operate the model. Every motor will run up smoothly until a second one is operated. The first motor then “stutters” and a fuse might blow, this could be indicative of a power surge. Any comments from the electronic experts among the group would be appreciated." First the battery: you may be right. Especially with 3 x4500 kV motors Since you are using 3 ESCs how about feeding each one from a slightly smaller (lower weight) battery? Precondition of course is that all three are equally charged to the same voltage and capacity AND have the same (or very very similar) internal resistance! Complicates the issue of course and motors with a lower kV rating and one power source may well be the better solution😉 Second the 'stutter': How and when did you switch in the second motor? If the first was still at 'Full Ahead', i.e. 'Pedal to the metal!, I might expect the battery voltage to dip and then recover with the sudden additional load and a sharp rise in total current drawn. But no particular excuse for a sudden current rise in the first motor ! Where was the fuse that blew? I suspect in the primary supply lead from the single battery🤓 since with brushless motors you can't fit individual fuse in their supply leads like you can with a brushed motor. BUT you can to the ESCs feeding them!!! You can't get a power surge from a battery, not like a surge on the mains network due to lightning etc! But you can get a voltage dip and recovery if you suddenly present it with an additional load😲 3) "The 3S battery was 10,500mAh and 40C; with this battery all three motors can be run at full speed together and fuses do not blow. It was also very heavy at 1700g, holding the model down." All run up together to full speed or 'switched in' as described above? There's a big difference between a gradual increasing of load on a power source and a sudden step increase! 4) "The motors are 4500 kV. On refection, think a slower motor around, perhaps 2000 kV would have been a better choice." I did think at the outset that 3 x 4500kV was perhaps a little ambitious😲 2000 - 2500 sounds much better, and more controllable👍 Then you could also get good performance results with a single battery of capacity lower and weight 👍 The function of the third (centre) motor for 'action speed' would also be more pronounced👍 5) "Would concur with comments by others that a simple single or two bladed propeller layout for this model is probably best - that is unless you want to capture the true scale layout. The centre propeller seems to have little effect on overall performance, (see above re 4500kV motors- Doug😉) although it will power the model quite nicely when operating by itself. Have had several suggestions about how best to use the centre propeller. Will think about them and decide later how to do this when I start to finish the model." As a 'Scale Purist' (as far as my skills and tools allow!) personally I would frown on the use of 2 blade props, much less only a single prop. Do that in a fictitious power boat if you will, but for 'Brave Borderer' ? 😡 Do her justice please😉 Many three screw (😲) boats (including the full size originals of this era) only used the third motor for additional manoeuvring speed in action situations. My personal experience of FACs (Fast Attack Craft) and FPBs (Fast Patrol Boats) over the last three decades shows me that the three screw configuration has been largely dropped, especially since the introduction of much more powerful engines such as improved diesels and gas turbines. Many use a combination of diesel, for cruising, and gas turbine for 'action speed', so called CODAG, COmbined Diesel And Gas turbine. 6) "The 2 blade Hi – speed propellers both increased performance and current draw. The model is more than fast enough with the original scale layout." As I believe the 2 blade props were of larger diameter (and perhaps also of larger pitch) than the 3 bladers the higher current draw is a logical conclusion! Stick with the scale config! 👍👍👍 7) "Will purchase a lighter, 3 S battery as that seems the best choice for performance and weight." 👍 but don't overdo it to the other extreme by reducing weight and therefore capacity too much😲 You want a decent sailing time don't you? 8) "Testing using the bare hull with a minimum of detail worked well. For a models with a complex power train, this is a good approach as access to the internals can be gained easily. Nothing worse that finishing a boat carefully just to find the performance disappointing. Then having to to rip it apart to make major modifications or adjustments!" Heartily agree 👍👍👍 Bon chance mon ami😊

Radio in a yacht by Haverlock Fleet Admiral!   Posted: 1 month ago
most 6V sail winches will work fine on 4.8 volts. if you NEED 6V then things get way more interesting. Check to see what voltage your receiver can handle ( some have built in BECs some not). in the event your radio needs nominal 5V ( 4.8) and sail winch 6V then you need a 6V power supply and a BEC to power the receiver. However some sail winches have a built in BEC so you can power your radio via the winch. ( BEC= battery eliminator circuit in effect a voltage regulator )

LiPo batteries by ronrees Sub-Lieutenant   Posted: 2 months ago
Hi all, Lithium-Ion and Li-Po batteries do not take kindly to being stored long term fully charged. When they are new they will do it but after 2 to 3 years of intermittant use, can start to swell a bit and that is where the dangers start. When you give these cells the final run of the season and they show a charge in the the 3.3 to 3.5 (or so) volts per cell then they can be stored relatively safely. (This is called a holding or factory charge) Re start them with a balanced charge before you next use them. Do not constantly fast charge them as thi could induce swelling of the pack earlier. The old Ammo box is a good idea, any strong metal box will do but store them where it does not get very hot or very cold and ideally not in the house. Lipo cells are accepted as hand luggage by most airlines and a holding charge is recommended when flying, so remember to take a small 12v DC balance charger or 'Intelligent' charger with you to other countries, you will always be sure of a power supply, like a car battery even where the mains voltage is different. Small black plug-in cell monitors are readily available from places like Component shop and are a good guide to cell condition. One is these is quite essential as we use these cells more and more. Cheers, hope this helps. Ron.

H.M.S. BRAVE BORDERER by RHBaker Fleet Admiral!   Posted: 2 months ago
Once the rudder, propeller and shafts were installed, the position of the motors could be established. A light aluminium bracket to hold all three was fabricated and bonded to the hull. Due to the high speed capability of the brushless motors, particular attention was paid to alignment. Also kept to the shortest prop. shafts that could be fitted to avoid whipping. Although the motor type might change, whatever is best will require a sound electrical installation as the current requirements for each brushless motor could reach 50 Amps. Wired each motor and ESC separately with its own dedicated fuse to give the maximum system protection. There is an extra fuse section allocated for auxiliary circuits, such as a cooling water pump and lights. Will try the original planned layout of 3 x 2835 motors with 30mm propellers and a 2S Li-Po battery first. Am hoping the reduced voltage will also make these motors more tractable. For the test program the three ESCs will be each controlled from an individual Rx channel. Once the final layout is determined, a more sophisticated and flexible control system can be installed. To minimize ballast, particularly around the stern, the battery will be housed as far into the bow as possible. After the test runs the final battery type, size and location can be established. To assess performance, hope to try both 2 and 3S Li-Po batteries. Planning to reduce heat build up by fitting cooling water jackets to the motors, these are easiest to instal at this stage so the wiring or mounts are not disturbed in the future. Have not decided the layout for the water circuit yet, but this easily can be added later. All that is needed now is the ice to melt off our local lakes so tests can commence.

LiPo batteries by MouldBuilder Commander   Posted: 3 months ago
Please can I get some advice on LiPo batteries. I intend to buy a 3300-5000mAh battery to run an offshore power boat model. I will be taking the battery with me to Hungary to use on my local river which I have found is ok as hand luggage properly protected from short circuit. My problem is that at present, I only go there three time a year so the battery would remain unused for 4 months at a time. If I leave the battery with a safety charge, will it last for four months unused or will it fall below the critical voltage. If it is felt that it will not hold the charge, I will have to carry it with me forward and back. Thanks.😊

Aerokits Patrol Torpedo Boat by RNinMunich Fleet Admiral!   Posted: 3 months ago
PS: Attached is the user manual for a typical Quickrun Car brushless ESC. Par 3 shows how to program it using the TX. Para 5 shows a table of the options available and the presets marked with black background! I used the programmer to set the Running Mode to Mode 3, i.e. No Brake between forward and reverse! the programmer is also useful for setting other parameters; esp number of battery cells and Low Voltage cut off. Hope this helps to know what to expect😉 Cheers Doug 😎

Aerokits Patrol Torpedo Boat by RNinMunich Fleet Admiral!   Posted: 3 months ago
Hi MB, can only say what I have which works and I ain't set the house on fire yet 😉 Not surprisingly for someone living in Munich both mine are from German companies! Robbe Power peak Uni 7 and Graupner Unimat 14. There are later versions of both around nowadays but you can still find these on Amazon / Ebay etc. Both of them have automated programmes for various Lithium types, NiMH / NiCad (not recommended these days!) and SLAs. Robbe is now defunct and their Marine stuff taken over by Graupner and marketed as RoMarin! Pics also show the Balancer Adaptor Boards, necessary to connect the balancer cable of the battery. This ensures that each cell is equally charged 😊 I also included in the pics the little battery Capacity Testers I use. They cost around a tenner and are very useful for checking the capacity before a run or charging, as well as the voltage and capacity of each cell, which gives an indication of the battery condition. I found some duff cells with the tester in a few batteries I'd only just bought 😡 When looking for / buying a charger look also for a LiPo Safe bag to charge them in. E.g. LiPo Guard. Charger may cost 50 quid upwards depending on how many charging outlets you want and how many Bells & Whistles. But I get on well with these two 😉 I like the Robbe version cos I can charge two LiPos at the same time. Also in the pics are a few of the charging cables I made up with gold 4mm bullet plugs for the charger end and Tamiya and BEC (for my Plastic magic stuff!) at the batt end. Such adaptor cables are also available 'ready made' but I just like fiddlin' 😊 Hope this helps, Cheers Doug 😎 Nearly forgot! Can't say for sure what current your motor will draw cos I don't know all the other details, but a 40" boat will need some shove! So I wouldn't go below the 5000mAH if you want a half decent run time. A 40" boat can carry a bit of weight! And batt power is more useful than pure ballast 😉 Recommend a little Wattmeter to check the max current draw - see last pic. Basic theory! A fully charged 5000mAh (or 5AH) batt can theoretically deliver 5A for one hour, or 10A for half an hour and so on! Say your set up draws 20A with the 'pedal to the metal' then a 5000mAH batt will 'theoretically' last 15 minutes. Theoretically cos other factors are in play; initial charge state, temperature, internal resistance of the cells, cable losses etc. The latter is why I only use gold connectors! The higher the batt capacity the higher the price and weight. So suggest you start with the 5000 and see how (long) it goes. Then check the weights of higher capacity batts (and the bank account / management approval😉) Bon chance mon ami!

Aerokits Patrol Torpedo Boat by MouldBuilder Commander   Posted: 3 months ago
Hello. I hope I can get a little help with battery choice. I have been reading the comments above and elsewhere on the site, and have decided to go along the LiPo route. I purchased the Turnigy 3648 1450kv brushless motor along with the Hobbyking brushless car ESC 100A w/reverse. I have done a little research on this battery but still do not know the exact battery I should be looking for. Please can you help with the following: What voltage should I be looking for. To have a reasonable useage period, can you advise on a suitable mAh rating. Please can you recommend a charger. Should I have a charge alarm. Should I have a monitor for cell voltage. Are there any other accessories I should have. Thanks in advance. Peter.😊