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lithium batterys from hong kong


jcbbracken
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Don't be using their claimed MAH rating as a guide because most of them are made for use with CCTV to supply very low current over a long period of time. Most of them are limited to about 1 amp draw capability.

 

 

You need the opposite. If the ones you look at show a thin cable and state they are for CCTV you will immediately see they are wrong for your needs.

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They work well with my micro magnets but you have to use a speed controller to start them or the current surge will trip them out. My little magnets run for hours on them and they weigh close to nothing. I will never use lead/acid again.

Would appreciate links / advice please to the batteries and "micro magnets" you use. Thanks.

Edited by Bobba
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  • 3 weeks later...

Hi JC

 

im an electronics engineer in the automotive field. and as my job ive needed to source lithium ion batteries. Ill try to keep this short.

 

lithium ion cells are 3.7v which gives you 11.1v for 3 cells and 14.8v for 4 cells the 4 cell would be ok but you would need to have a regulator as this would increase magnet speed a little. lithium ion are very expensive compared with sealed lead acid and they do need special charging circuits which is not a problem but it does add expense. Lithium ion from china definatley no i have sampled hundred of cells from china and all but a few have been less than 1/10th there stated rating. you can source good cells from china but most are underrated and all of the cells tested from ebay sites were not good.

 

I know they are heavier but a 7Ah SLA will do the job better they are cheaper and easier to charge.

 

I havent shot for a number of years and i forget what ball ache it is lugging things around a field. I'm getting older and the problem is worse now as then all i had was some deeks some skrim, gun and cartridges with the equipment now i decicded enough was enough and adapted a golf trolley which i bought for a fiver my life was changed.

 

ill post pics if you want to copy it i also made my own FUD's for a quarter of the price the space saving was huge.

 

Hope this helps

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Hi JC

 

im an electronics engineer in the automotive field. and as my job ive needed to source lithium ion batteries. Ill try to keep this short.

 

lithium ion cells are 3.7v which gives you 11.1v for 3 cells and 14.8v for 4 cells the 4 cell would be ok but you would need to have a regulator as this would increase magnet speed a little. lithium ion are very expensive compared with sealed lead acid and they do need special charging circuits which is not a problem but it does add expense. Lithium ion from china definatley no i have sampled hundred of cells from china and all but a few have been less than 1/10th there stated rating. you can source good cells from china but most are underrated and all of the cells tested from ebay sites were not good.

 

I know they are heavier but a 7Ah SLA will do the job better they are cheaper and easier to charge.

 

I havent shot for a number of years and i forget what ball ache it is lugging things around a field. I'm getting older and the problem is worse now as then all i had was some deeks some skrim, gun and cartridges with the equipment now i decicded enough was enough and adapted a golf trolley which i bought for a fiver my life was changed.

 

ill post pics if you want to copy it i also made my own FUD's for a quarter of the price the space saving was huge.

 

Hope this helps

 

I think we all know that the Chinese batteries have a lower amperage than stated but the fact is that a 6.8a/h one will spin my home made magnets for a few hours and a flapper all day despite being somewhere near the size and weight of a pack of cigarettes and less than 20 quid. If you want a better one buy a Deben for around £100 depending on what amperage you want. Even if they only lasted one season it would still be worth it to me and I shall never take a heavy lead acid battery out again.

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Hi JC

 

im an electronics engineer in the automotive field. and as my job ive needed to source lithium ion batteries. Ill try to keep this short.

 

lithium ion cells are 3.7v which gives you 11.1v for 3 cells and 14.8v for 4 cells the 4 cell would be ok but you would need to have a regulator as this would increase magnet speed a little. lithium ion are very expensive compared with sealed lead acid and they do need special charging circuits which is not a problem but it does add expense. Lithium ion from china definatley no i have sampled hundred of cells from china and all but a few have been less than 1/10th there stated rating. you can source good cells from china but most are underrated and all of the cells tested from ebay sites were not good.

 

I know they are heavier but a 7Ah SLA will do the job better they are cheaper and easier to charge.

 

I havent shot for a number of years and i forget what ball ache it is lugging things around a field. I'm getting older and the problem is worse now as then all i had was some deeks some skrim, gun and cartridges with the equipment now i decicded enough was enough and adapted a golf trolley which i bought for a fiver my life was changed.

 

ill post pics if you want to copy it i also made my own FUD's for a quarter of the price the space saving was huge.

 

Hope this helps

 

I would be interested in seeing pics :)

 

Thank you!!

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I have used three cell and four cell lithium ion cells to power electric flight model aircraft, they deliver high power short burst amps fine , but if you demand continuous high amp they tend to break down very quickly, recharging has to be done through specialised chargers which monitor and balance individual cells,

These cells have been known to swell, overheat and even catch fire if things go wrong

When I started looking at power for my flappers and magnet I tried out a pair of these batteries linked in parallel , they got very hot after a short time and on the magnet only lasted a short time, eventually I gave up on them , opting for a gell pack golf trolley 12 volt battery, it charges quickly, holds power well and is not too heavy on those longer walks,

I have since built a trolley out of an electric golf trolley with a fishing box mounted on top, shortened the chassis, built in a back rest and put the battery on crocodile clips ,

I simply fit the gell pack inside the box, fill up the trolley with most of my gear, steer it to my chosen site using the variable speed controller, unload, set up and run the magnet for up to 5 hours and there is still sufficient power in the battery to drive the trolley, loaded, back to the car.

My only problem which I have not yet solved is that the drive wheel tyres are smooth, so fail to grip well on rough ground, so I am searching for a decent pair of wheels with mud grip tyres, but otherwise a great bit of kit. :yes::yes:

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