Harbor Freight $10 1700mah 18v battery packs

[vanilla ice]

So I'm guessing these are just 15 pieces of an economy 1.2v 1700mah nicad in a plastic container. Is this a good deal at $10?? Seems a decent price, I mean if I were going to ditch the SLAs.

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=90121

So ten of these 2s5p would be 36v 8500mah... at $100.

 

[xyster]

I bought one of these to replace the cells in an 18v powertool -- works great for that.

Nicad and NiMH can not be charged in parallel without added measures such as diodes or switches to isolate the series-strings for charging. I think you could make a very economical pack with these if you were willing to spend the time to separate each 36v string with diodes to prevent one string from charging another; and were willing to have a separate charging port for each string.

 

[safe]

18 volt * 2 = 36 volt

1.7 Ah * 20 = 34 Ah

Price would be: $10 * 2 * 20 = $400

That looks to be lower in price than just about anything... am I wrong?

Buying the "D" cells would run about $600 for that normally.

 

[xyster]

That looks to be lower in price than just about anything... am I wrong?

I think you're correct. I started a thread about these three months ago where the price and charging issues are also discussed:
http://endless-sphere.com/forums/viewtopic.php?t=1179&highlight=nicad

 

[ort5]

You could also spend $5 more and get a charger and a drill!

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=93440

 

[vanilla ice]

Ah didn't see that thread. Good stuff.

I would retain the plastic cases if I were using these. As was said in the earlier thread on these, close as it gets to SLA pricing right here.

I have one of the above drills with 2 batts, thats why this caught my attention. The package with the charger seems like the way to go. If you can manage to sell off the drills for $5 each you get a free charger.

 

[CGameProgrammer]

It's nearly as cheap as lead-acid. B&B lead-acid batteries are around $35 for 12V 12Ah for $0.24 per Wh; these NiMH batteries are $0.32. That's still incredibly cheap; NiMH is usually more like $0.80 or more from what I've seen.

 

[xyster]

It's nearly as cheap as lead-acid. B&B lead-acid batteries are around $35 for 12V 12Ah for $0.24 per Wh; these NiMH batteries are $0.32. That's still incredibly cheap; NiMH is usually more like $0.80 or more from what I've seen.

When per-mile cost is factored over the life of the battery, Nicad is usually much cheaper than SLA. Nicad possesses upwards of 10 times the cycle life of SLA for a few times the initial cost. Factor it per-mile per-pound, and Nicad looks that much better.

http://www.batteryuniversity.com/parttwo-36.htm

Nickel-cadmium

In terms of life cycling, standard nickel Cadmium is the most enduring battery. Figure 1 illustrates the capacity, internal resistance and self-discharge of a 7.2V, 900mA nickel-cadmium battery with standard cells. Due to time constraints, the test was terminated after 2300 cycles. The capacity remained steady, the internal resistance stayed flat at 75mW and the self-discharge was stable. This battery receives a grade 'A' for almost perfect performance. It should be noted that nickel-cadmium has a moderate energy density, requires periodic full discharges and contains toxic metals.

 

[vanilla ice]

I think I'm going to dissect my two harbor freight packs and do the 30 cells up in 5s6p for 6v 10.2a in series with my stock currie 24v 10a stock setup. Hybrid style SLA/nicad. The extra mph should keep me entertained for couple weeks.

Nicad and NiMH can not be charged in parallel without added measures such as diodes or switches to isolate the series-strings for charging.

Why can you not leave these in parallel while charging??? Thats a bummer.

 

[TylerDurden]

Why can you not leave these in parallel while charging??? Thats a bummer.

Ummmmm.....

Something about one cell hogging all the current and going 'bang'.

:?

 

[vanilla ice]

I'm glad I have this forum to prevent that kind of carnage in my home. Had no idea... Vanilla ice harbor freight pack dismantle tentatively scheduled for Sunday 10:00. Results to follow.

I think theres a sentence in the previous paragraph there that's never been uttered in the history of the universe.

 

[Dalecv]

I own a couple of those Harbor Freight 18V drills. When I bought them a year or so ago you could buy an extra battery pack for $5, but of course there weren't any batteries in stock at the store.

The charger is a piece of work, it doesn't automatically shut off when the battery is fully charged and the instructions say not to leave the battery in the charger for more than 6 or 7 hours. Of course I didn't read the instructions, plugged the battery pack in and went off and forgot about it for a few days.

 

[vanilla ice]

Well I found out last night my two packs are actually only 1200mah, so I'm just going to leave them be as drill batteries.

I know we don't have detailed specs on these 1700mah harbor freight cells, but I figure you guys would have a pretty good idea on this- How do these nicads stack up as far as max current against SLA, Nimh, and the more exotic stuff?

 

[vanilla ice]

HF item #93440 is $13.99 for drill, 5hr charger, and 18v battery. Walk in price only, good until Oct. 15th.

Hacksaw the drills in half and epoxy the battery receptacle portions together inside a bike rack bag...

 

[monster]

so are drill batteries always the way to go? they come with a free charger and a drill we can sell. what are the tips for buying drills for their batteries? i see a lot of drills for sale on ebay advertised as "naked" ie without batteries, is this from all the people using their packs for EV's?

 

[TylerDurden]

so are drill batteries always the way to go? they come with a free charger and a drill we can sell. what are the tips for buying drills for their batteries? i see a lot of drills for sale on ebay advertised as "naked" ie without batteries, is this from all the people using their packs for EV's?

Depends. A lot of ebay stuff is nicked, so not all the goodies com along.