Tenergy 8 pcs of Premium D Size 10,000mAh High Capacity High Rate NiMH Rechargeable Batteries - UL Certified

I own 8 of these great rechargable batteries. They work very well and keep the charge a long time used in a baby mobile. The issue is, that the baby mobile draws a very low current and the batteries get exhaustive discharged and appear dead to the charger. After refreshing, the dead battery seems to be fine. 4 stars because of the high price. How to refresh a "dead" battery: I read on a discussion board, you place the "dead" and an equal sized battery in your charger. Take a paperclip and connect the plus(+)-poles of these two batteries. Wait 15 minutes and remove the paperclip. The "dead" battery keeps charging. Update 06/13/2016: The price is now reasonable. Changing to five stars. The best is, I have bought these batteries 4 years ago and we used them constantly for a crib white noise toy. Now after four years 3 of the eight show signs of fatigue and will not hold the charge much longer. Well worth the price. Go for it!

I have used the 8 pcs of Premium Tenergy D Size 10,000mAh High Capacity High Rate NiMH Rechargeable Batteries for over a year, and have been pleased. I have seen this brand used on TV and movie sets, and already know the quality - this is a best-in-class item. Around the house I use them for the lovely, but energy hog "Luminara" flameless candles - which are also best-in-class ( and used at theme parts, movies, TV and Broadway). After a year++ of use, I can assure you that that the product is well worth your consideration. To be fair, they are costly, but in this case, you DO get what you pay for - excellent results! You will need to get a premium charger, but will be glad you made the investment. During the holiday season, I needed/wanted to include D battery packs for several gifts. Suggesting re-chargables can be a tough sell for some. They wanted the regular battery set up. Ugh! I easily spent around $8.50 per 4-pack, and freaked-out when I needed one more and bought a pack of regular battries at a quick shop store (think "numbers" LOL) and paid close to $12.00. Just do the math here. Bottom line: * The product is heavy, but are REAL D cell/s unlilke other brands which encase AA's to create the D shape .. * It is a brand studio's use, it is a professional item. * Will save you money over a short period of time. * You can use them over-and-over. * Outstanding quality, and a trusted brand. Get the good ones here, you will NOT be sorry. Over time, it can be kind of fun to quantify your savings, too. I can ASSURE you that studio's do!

[Capacity:] Tenergy seems to have world wide the highest rated capacities for rechargeable NI-MH batteries. Looks like Tenergy has almost maxed out of whats technically possible. No other maker has these capacity range, hats off !! Even the best Japanese makers have max roughly only 60% capacity (5700 mah), again respect for this !! It's awesome how much capacity this rechargeable batteries have. [Weight:] Lets face it, batteries are heavy. Capacity limits and weight are probably their worst obstacles. Fortunately the extended capacity plays as advantage as you might come by with one battery pack where you used two or more in the past. This comes in VERY handy when either every gram counts or stamina is everything. [Charging:] We all know that increased capacity not only gives you better mileage but also requires fewer (but long) charging cycles. Generally speaking high capacity is a good thing but long charging times might be a turn off when you are in hurry. In addition quick charging or charging to often (to early) might decrease life cycle of the battery (read: damage it). So it makes sense that you also invest in an "intelligent" charger, that checks the battery status, de-charges it controlled and recharges it gently. This way your investment is protected. [Usage:] So far I have used those batteries and haven't realized any significant drop of capacity. Its to early to tell the long term quality of the product, however so far everything is indicating a good quality product. I will update this section in regular intervals to indicate any capacity changes. ---[Summary and target user:]--- I am conservative. For the technology and capacity alone I would easily give 5 or even 6 Stars. I understand that 10.000mah is a capacity that is almost unheard off and more likely bikes or even small car batteries have it. For the average user even 50$ + charger cost is a deep price to pay, so its not a deal for occasional uses. HOWEVER, for power sucking heavy usage this is a steal, especially if you MUST HAVE the extended stamina. 5 Stars for heavy users 4 Stars for average users ((Reason is initial cost) Enjoy the ride !!

I use them in an electronic cat door, and they outlast regular batteries before needing re-charge. This is great because changing the batteries in this door is a pain. The product is exactly as described. I expect they will easily pay for themselves plus reducing waste/garbage.

Great

last longer than the rest will order more