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Battery Run Life & Charge Time

Posted: Fri Nov 28, 2014 11:50 am
by Merlin707
Hi guys,

Just seen this on eBay, it's for 3 6800mAh rechargeable batteries, see below:

Battery Features:
Brand new 6800mAh 7.2V NiMH rechargeable battery
* 6800mAh 7.2V rechargeable Battery
* No memory effect, recharge up to 1000 cycles
* 100% high quality battery cells
* 100% Q.C. of every battery
* Manufactured by Hi-Capacity power products.
* Size: Size: 13 x 4.8 x 2.5 (cm) / 5.12 x 1.89 x 0.98 (in)
* Weight:Approx 400g (1pcs)

Package included:
3 x 6800mAh 7.2V NiMH rechargeable battery


My question is:
1. How long will these take to charge with a Turnigy Accucel 6?
2. How long will I get running time in my tanks?

Re: Battery Run Life & Charge Time

Posted: Fri Nov 28, 2014 12:17 pm
by Tankbear
Charge time depends on charge rate, as a rule of thumb charge rate of 1A (1000mA) will take 6.8 hours. Therefore 2A 3.4 hours and so on.

Run time varies to how you drive it, My plastic HL tiger I got 20-40 minutes from the 1700mAh battery there since these batteries are 4 times bigger expect 4 times the running time.

One word of warning about batteries from Ebay “Fake” if the deal seems cheap chances are your getting conned. I bought MiMH batteries from ebay in the past and both well below stated capacity (3800 turned out 1300, and 5000 turned out 3000)

Ian.

Re: Battery Run Life & Charge Time

Posted: Fri Nov 28, 2014 12:23 pm
by Merlin707
Hi Ian,

Thanks for the heads up, these are £38 for the 3.

Would you say these are too cheap for the power output?

They are branded up as Tamiya.

Re: Battery Run Life & Charge Time

Posted: Fri Nov 28, 2014 12:32 pm
by Jake79
I'd of thought they were referring to the connection...I haven't seen a batt made by Tam before.....

Re: Battery Run Life & Charge Time

Posted: Fri Nov 28, 2014 12:46 pm
by Tankbear
Do sound cheap to me, and like Jake79 says probably Tamiya plug rather than brand.

Bit of topic but if your after high capacity then LiPo batteries are way to go. Bit more expensive at first as need a charger which does LiPo but the performance boost from changing to LiPo is significant.

Ian.

Re: Battery Run Life & Charge Time

Posted: Fri Nov 28, 2014 12:52 pm
by MichaelC
Merlin,

Can you send the link or the name of the seller ? I have gotten some 6800s before and they do seem to last, not that I know how long 6800 will last and they might not be 6800 in reality like Tankbear says but even if it is 5800 and 5000 it is still pretty cheap. I guess just buy it with a grain of salt perhaps ?

MichaelC.

Re: Battery Run Life & Charge Time

Posted: Fri Nov 28, 2014 1:07 pm
by Tankbear
MichaelC wrote:not that I know how long 6800 will last.
Smart chargers will tell you how much charge it puts into a charger (also have a charge limit so cannot put to much into a batter)

Or other way is if you know your charger output i.e. 1A or 2A times this by the hours it takes to fully charge.

So say your charger is 2A output and charges a flat battery to full in 2.5 hours. Capacity = 5000mAh

Ian.

Re: Battery Run Life & Charge Time

Posted: Fri Nov 28, 2014 1:46 pm
by jarndice
What aggravates me is battery size, I can run a decent sized reasonably cheap NI-MH or a large capacity LI-PO in the battery bay of my Tanks and the bay size is pretty much standard but I have to buy a different size battery for my aircraft, the CofG taking care of location and keeping them generally smaller. I wish I could use the same batteries in both my Tanks and my Aircraft which by the way are 1/10 scale, :problem: shaun

Re: Battery Run Life & Charge Time

Posted: Fri Nov 28, 2014 2:04 pm
by tomhugill
I use my aircraft batteries in my boats. The constraint would be voltage I would imagine as most planes seem to run on 3s or above.

Re: Battery Run Life & Charge Time

Posted: Sat Nov 29, 2014 3:29 pm
by ALPHA
I would go with everything Tankbear said Merlin...... but the point I agree with most is to move to LIPO .... you just can't beat the performance ;)

ALPH