Batteryspace RC Car packs test data

3 posts / 0 new
Last post
andrew
andrew's picture
Offline
Last seen: 11 years 9 months ago
Joined: Tuesday, November 28, 2006 - 17:21
Points: 1361
Batteryspace RC Car packs test data

I did some load testing on the 6-Cell RC battery packs from http://www.batteryspace.com because I am anticipating using them to replace lead-acid batteries in my motorcycle. I just need to work out how to build a BMS and charge them.

NiMH 3ah 7.2v test http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=70
After Connector cut off
Charged at 2 amps for few minutes before test
Open C. 7.8v
30 amps: 5.83
50 amps: 5.10
75 amps: 3.174
The load test was only momentary

NiCad 1.7 ah 7.2v test http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=89
Battery 1 after overcharge for about 20 hrs at 250 ma (oops!)
After Connector cut off
Battery feels warm to hot
Open C. 8.41v
30 amps: 6.5
50 amps: 5.42
80 amps: 3.61
The load was only momentary.

Battery 2 after charge at 250 ma for 7hrs
Connector cut off
Battery feels slightly warmer than room temp
Open C. 8.47v
30 amps: 6.61
50 amps: 5.53
80 amps: 3.75

circuitsmith
circuitsmith's picture
Offline
Last seen: 5 months 2 weeks ago
Joined: Tuesday, November 21, 2006 - 07:24
Points: 31
Re: Batteryspace RC Car packs test data

How short was momentary? I'm surprised you could draw 25C from their NiMH with out problems. 63 milliohms @ 30A for either of their packs = 10 milliohm per cell with interconnects.

I'm using Batteryspace 24V sub-C packs (mine are the earlier 3.3AH version):
http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=2759

I measured 120 milliohm resistance in these packs. That would be 3.6V sag @ 30A.

andrew
andrew's picture
Offline
Last seen: 11 years 9 months ago
Joined: Tuesday, November 28, 2006 - 17:21
Points: 1361
Re: Batteryspace RC Car packs test data

circuitsmith,

I'd cut the Tamiya connector as I found they add considerable resistance.

Each load test was for about 2 sec, and I did the lower rates first. I was surprised I got 47C out of the NiCad pack. That "sintered" electrode must do something. Note that the NiCads have 16 AWG wire, while the NiMH has 14 AWG.

---
Avatar taken from http://www.electricmotorbike.org/
Anyone got one they might want to sell?
My KZ750 Project: here E.T.A. 1 mo

[url=/forum-topic/motorcycles-and-large-scooters/587-my-kz750-electric-motorcycle-project]KZ750 Motorcycle Conversion[/url]
[url=/forum-topic/motorcycles-and-large-scooters/588-fixing-my-chinese-scooter]900 watt scooter[/url]
Pic from http://www.electri

Log in or register to post comments

Use code"Solar22" and enjoy 12% off for all solar Kits.


Who's online

There are currently 0 users online.

Who's new

  • rima7777
  • leoke
  • Nicolay
  • Nickel
  • Florix

Support V is for Voltage